U.S. patent application number 10/841662 was filed with the patent office on 2005-11-10 for film-forming compositions substantially free of organic solvent, multi-layer composite coatings and related methods.
Invention is credited to Anderson, Lawrence G., Grolemund, Mary Beth, Hockswender, Thomas R., Kania, Charles M., Martin, Roxalana L., Novak, Carolyn A.K., Ragan, Deirdre, Terrago, Gina M., Tucker, Mark A., Williams, Alicia.
Application Number | 20050249958 10/841662 |
Document ID | / |
Family ID | 34968429 |
Filed Date | 2005-11-10 |
United States Patent
Application |
20050249958 |
Kind Code |
A1 |
Kania, Charles M. ; et
al. |
November 10, 2005 |
Film-forming compositions substantially free of organic solvent,
multi-layer composite coatings and related methods
Abstract
Film-forming compositions are disclosed that are substantially
free of organic solvent. The film-forming compositions include a
resinous binder and at least one water dilutable additive including
the reaction product of (i) a reactant including at least one
isocyanate functional group with (ii) an active hydrogen containing
alkoxypolyalkylene compound. Also disclosed are multi-layer
composite coatings that include such film-forming compositions and
methods of applying such multi-component composite coatings to a
substrate.
Inventors: |
Kania, Charles M.; (Natrona
Heights, PA) ; Martin, Roxalana L.; (Pittsburgh,
PA) ; Novak, Carolyn A.K.; (Gibsonia, PA) ;
Hockswender, Thomas R.; (Gibsonia, PA) ; Tucker, Mark
A.; (Gibsonia, PA) ; Grolemund, Mary Beth;
(Sarver, PA) ; Ragan, Deirdre; (Gibsonia, PA)
; Williams, Alicia; (Greensboro, NC) ; Terrago,
Gina M.; (Pittsburgh, PA) ; Anderson, Lawrence
G.; (Pittsburgh, PA) |
Correspondence
Address: |
PPG INDUSTRIES, INC.
Intellctual Property - Law Dept.
One PPG Place
Pittsburgh
PA
15272
US
|
Family ID: |
34968429 |
Appl. No.: |
10/841662 |
Filed: |
May 7, 2004 |
Current U.S.
Class: |
428/423.1 |
Current CPC
Class: |
C08G 18/706 20130101;
C08G 18/283 20130101; C09D 175/04 20130101; Y10T 428/31551
20150401 |
Class at
Publication: |
428/423.1 |
International
Class: |
B05D 003/02 |
Claims
We claim:
1. A film-forming composition that is substantially free of organic
solvent, comprising: a resinous binder; and at least one first
water dilutable additive comprising the reaction product of (i) a
reactant comprising at least one isocyanate functional group with
(ii) an active hydrogen containing alkoxypolyalkylene compound.
2. The film-forming composition of claim 1 wherein the reactant (i)
comprises a polyisocyanate selected from the group consisting of
aliphatic polyisocyanates, cycloaliphatic polyisocyanates, aromatic
polyisocyanates, and mixtures thereof.
3. The film-forming composition of claim 2, wherein the reactant
(i) comprises a diisocyanate.
4. The film-forming composition of claim 3, wherein the
diisocyanate is isophorone diisocyanate.
5. The film-forming composition of claim 1, wherein the reactant
(ii) comprises an alkoxyethylene glycol.
6. The film-forming composition of claim 5, wherein the reactant
(ii) comprises a methoxypolyethylene glycol.
7. The film-forming composition of claim 1, wherein the first water
dilutable additive is present in the film-forming composition in an
amount ranging from about 0.01 to about 10 percent by weight based
upon the total weight of resin solids present in the film-forming
composition.
8. The film-forming composition of claim 1, further comprising at
least one second water dilutable additive which is different from
the at least one first water dilutable additive, wherein the second
water dilutable additive comprises a reactive functional
group-containing polysiloxane.
9. The film-forming composition of claim 8 wherein the second water
dilutable additive comprising a reactive functional
group-containing polysiloxane comprises a carboxylic acid
functional group-containing polysiloxane.
10. The film-forming composition of claim 9 wherein the carboxylic
acid functional group-containing polysiloxane has the following
general structural formula: 4where m is at least 1; m' is 0 to 50;
n is 0 to 50; R is selected from the group consisting of OH and
monovalent hydrocarbon groups connected to the silicon atoms; Ra
has the following structure: R.sub.1--O--X wherein R.sub.1 is
alkylene, oxyalkylene or alkylene aryl; and X contains COOH
functional groups.
11. The film-forming composition of claim 10 wherein the carboxylic
acid functional group-containing polysiloxane is the reaction
product of the following: (A) a polysiloxane polyol of the
following general formula: 5where m is at least 1; m' is 0 to 50; n
is 0 to 50; R is selected from the group consisting of H, OH and
monovalent hydrocarbon groups connected to the silicon atoms; Rb
has the following structure: R.sub.1--O--Y wherein R.sub.1 is
alkylene, oxyalkylene or alkylene aryl; and the moiety Y is H,
mono-hydroxy-substituted alkyl or oxyalkyl, or has the structure of
CH.sub.2C(R.sub.2).sub.a(R.sub.3).sub.b wherein R.sub.2 is
CH.sub.2OH, R.sub.3 is an alkyl group containing from 1 to 4 carbon
atoms, a is 2 or 3, and b is 0 or 1; and (B) at least one
polycarboxylic acid or anhydride.
12. The film-forming composition of claim 11 wherein reactant (B)
comprises an anhydride.
13. The film-forming composition of claim 12 wherein reactant (B)
is selected from the group consisting of hexahydrophthalic
anhydride, methyl hexahydrophthalic anhydride, phthalic anhydride,
trimellitic anhydride, succinic anhydride, alkenyl succinic
anhydride and substituted alkenyl succinic anhydride, and mixtures
thereof.
14. The film-forming composition of claim 8 wherein the second
water dilutable additive comprising a reactive functional
group-containing polysiloxane is present in the film forming
composition in an amount ranging from 0.1 to 10.0 percent by weight
based on the weight of total solids present in the film-forming
composition.
15. The film-forming composition of claim 14 wherein the second
water dilutable additive comprising a reactive functional
group-containing polysiloxane is present in the film forming
composition in an amount ranging from 0.1 to 5.0 percent by weight
based on the weight of total solids present in the film-forming
composition.
16. The film-forming composition of claim 15 wherein the second
water dilutable additive comprising a reactive functional
group-containing polysiloxane is present in the film forming
composition in an amount ranging from 0.1 to 1.0 percent by weight
based on the weight of total solids present in the film-forming
composition.
17. The film-forming composition of claim 1, wherein the resinous
binder comprises (1) at least one reactive functional
group-containing polymer and (2) at least one crosslinking agent
having functional groups reactive with the functional groups of the
polymer.
18. The film-forming composition of claim 17, wherein the polymer
(1) is selected from the group consisting of acrylic polymers,
polyester polymers, polyurethane polymers, polyether polymers,
polysiloxane polymers, polyepoxide polymers, copolymers thereof,
and mixtures thereof.
19. The film-forming composition of claim 17, wherein the polymer
(1) contains functional groups selected from the group consisting
of hydroxyl groups, carbamate groups, carboxyl groups, isocyanate
groups, amino groups, amido groups, and combinations thereof.
20. The film forming composition of claim 1, wherein the resinous
binder comprises an aqueous dispersion comprising polymeric
microparticles that are adapted to react with a crosslinking
agent.
21. The film-forming composition of claim 20, wherein the polymeric
microparticles are prepared from at least one polymer having
reactive functional groups and at least one crosslinking agent.
22. The film forming composition of claim 21, wherein the polymer
comprises a substantially hydrophobic polymer.
23. The film-forming composition of claim 1, wherein the resinous
binder comprises an aqueous dispersion of polymeric microparticles
prepared from (1) one or more reaction products of ethylenically
unsaturated monomers, at least one of which contains at least one
acid functional group, (2) one or more polymers different from (1)
and (3), and (3) one or more crosslinking agents having functional
groups reactive with those of at least one of the reaction product
(1) and the polymer (2).
24. The film-forming composition of claim 23, wherein the polymer
(2) comprises a substantially hydrophobic polymer and the
crosslinking agent (3) comprises a substantially hydrophobic
crosslinking agent.
25. The film-forming composition of claim 1, wherein the resinous
binder comprises an aqueous dispersion of polymeric microparticles
prepared from (A) at least one functional group-containing reaction
product of polymerizable, ethylenically unsaturated monomers; and
(B) at least one reactive organopolysiloxane.
26. The film forming composition of claim 25, wherein the polymeric
microparticles are also prepared from (C) at least one
substantially hydrophobic crosslinking agent.
27. The film-forming composition of claim 26, wherein (B) comprises
at least one of the following structural unit:
R.sup.1.sub.nR.sup.2.sub.m--(- --Si--O).sub.(4-n-m)/2 wherein m and
n each represent a positive number fulfilling the requirements of:
0<n<4; 0<m<4; and 2.ltoreq.m+n)<4; R.sup.1
represents H, OH or monovalent hydrocarbon groups; and R.sup.2
represents a monovalent reactive functional group-containing
organic moiety.
28. The film-forming composition of claim 25, wherein the reactive
organopolysiloxane is substantially hydrophobic.
29. The film-forming composition of claim 1, further comprising at
least one crosslinking agent that is adapted to be at least one of
water soluble and water dispersible.
30. The film-forming composition of claim 29, wherein the
crosslinking agent that is adapted to be at least one of water
soluble and water dispersible is selected from the group consisting
of polyisocyanates, aminoplast resins, and mixtures thereof.
31. The film-forming compositions of claim 29, wherein the
crosslinking agent that is adapted to be at least one of water
soluble and water dispersible is present in the film-forming
composition in an amount ranging from 0 to 70 percent by weight
based on total weight of resin solids present in the
composition.
32. The film-forming composition of claim 1, further comprising an
aqueous dispersion of polymeric microparticles prepared by emulsion
polymerization of a monomeric composition comprising (1) at least
10 percent by weight of one or more vinyl aromatic compounds; (2)
0.1 to 10 percent by weight of one or more carboxylic acid
functional polymerizable, ethylenically unsaturated monomers; (3) 0
to 10 percent by weight of one or more polymerizable monomers
having one or more functional groups which are capable of reacting
to form crosslinks; and (4) one or more polymerizable ethylenically
unsaturated monomers, where the weight percentages are based on
total weight of monomers present in the monomeric composition, and
wherein each of (1), (2), (3) and (4) above is different one from
the other, and at least one of (3) and (4) is present in the
monomeric composition.
33. The film-forming composition of claim 1, further comprising
inorganic particles selected from fumed silica, amorphous silica,
colloidal silica, alumina, colloidal alumina, titanium dioxide,
zirconia, colloidal zirconia and mixtures thereof.
34. The film-forming composition of claim 33, wherein the inorganic
particles have an average particle size ranging from 1 to 1000
nanometers prior to incorporation into the composition.
35. The film-forming composition of claim 33, wherein the inorganic
particles have an average particle size ranging from 1 to 10
microns prior to incorporation into the composition.
36. The film-forming composition of claim 1, further comprising at
least one pigment.
37. A substrate having at least one surface at least partially
coated with the film-forming composition of claim 1.
38. A film-forming composition that is substantially free of
organic solvent, comprising: a resinous binder comprising an
aqueous dispersion comprising polymeric microparticles that are
adapted to react with a crosslinking agent; at least one first
water dilutable additive comprising the reaction product of (i) a
reactant comprising at least one isocyanate functional group with
(ii) an active hydrogen containing alkoxypolyalkylene compound; and
at least one second water dilutable additive that is different from
the first water dilutable additive, wherein the second water
dilutable additive comprises a reactive carboxylic acid functional
group-containing polysiloxane.
39. The film-forming composition of claim 38, wherein the reactant
(i) comprises a polyisocyanate selected from the group consisting
of aliphatic polyisocyanates, cycloaliphatic polyisocyanates,
aromatic polyisocyanates, and mixtures thereof.
40. The film-forming composition of claim 39, wherein the reactant
(i) comprises a diisocyanate.
41. The film-forming composition of claim 38, wherein the reactant
(ii) comprises an alkoxyethylene glycol.
42. The film-forming composition of claim 38, wherein the polymeric
microparticles are prepared from (A) at least one polymer having
reactive functional groups and (B) at least one crosslinking
agent.
43. The film-forming composition of claim 38 further comprising at
least one crosslinking agent that is adapted to be at least one of
water soluble and water dispersable.
44. The film-forming composition of claim 38 further comprising an
aqueous dispersion of polymeric microparticles prepared by emulsion
polymerization of a monomeric composition comprising (1) at least
10 percent by weight of one or more vinyl aromatic compounds; (2) 0
to 10 percent by weight of one or more carboxylic acid functional
polymerizable, ethylenically unsaturated monomers; (3) 0 to 10
percent by weight of one or more polymerizable monomers having one
or more functional groups which are capable of reacting to form
crosslinks; and (4) one or more polymerizable ethylenically
unsaturated monomers, where the weight percentages are based on
total weight of monomers present in the monomeric composition, and
wherein each of (1), (2), (3) and (4) above is different one from
the other, and at least one of (3) and (4) is present in the
monomeric composition.
45. A film-forming composition that is substantially free of
organic solvent, comprising: a resinous binder comprising an
aqueous dispersion comprising polymeric microparticles that are
adapted to react with a crosslinking agent; at least one first
water dilutable additive comprising the reaction product of (i) a
reactant comprising at least one isocyanate functional group with
(ii) an active hydrogen containing alkoxypolyalkylene compound; at
least one second water dilutable additive that is different from
the first water dilutable additive, wherein the second water
dilutable additive comprises a reactive carboxylic acid functional
group-containing polysiloxane; at least one crosslinking agent that
is adapted to be at least one of water soluble and water
dispersable; and an aqueous dispersion polymeric microparticles
prepared by emulsion polymerization of a monomeric composition
comprising (1) at least 10 percent by weight of one or more vinyl
aromatic compounds; (2) 0 to 10 percent by weight of one or more
carboxylic acid functional polymerizable, ethylenically unsaturated
monomers; (3) 0 to 10 percent by weight of one or more
polymerizable monomers having one or more functional groups which
are capable of reacting to form crosslinks; and (4) one or more
polymerizable ethylenically unsaturated monomers, where the weight
percentages are based on total weight of monomers present in the
monomeric composition, and wherein each of (1), (2), (3) and (4)
above is different one from the other, and at least one of (3) and
(4) is present in the monomeric composition.
46. A multi-layer composite coating comprising a basecoat deposited
from at least one basecoat film-forming composition and a topcoat
composition applied over at least a portion of the basecoat in
which the topcoat is deposited from at least one topcoat
film-forming composition that is substantially free of organic
solvent, the topcoat film-forming composition comprising: a
resinous binder; and at least one first water dilutable additive
comprising the reaction product of (i) a reactant comprising at
least one isocyanate functional group with (ii) an active hydrogen
containing alkoxypolyalkylene compound.
47. The multi-layer composite coating of claim 46, wherein the
basecoat is deposited from at least one film-forming composition
comprising at least one pigment.
48. The multi-layer composite coating of claim 46, wherein the
topcoat is transparent.
49. A substrate having at least one surface at least partially
coated with the multi-layer composite coating of claim 46.
50. The multi-layer composite coating of claim 46 wherein the
reactant (i) comprises a polyisocyanate selected from the group
consisting of aliphatic polyisocyanates, cycloaliphatic
polyisocyanates, aromatic polyisocyanates, and mixtures
thereof.
51. The multi-layer composite coating of claim 50, wherein the
reactant (i) comprises a diisocyanate.
52. The multi-layer composite coating of claim 46, wherein the
reactant (ii) comprises an alkoxyethylene glycol.
53. The multi-layer composite coating of claim 46, wherein the
first water dilutable additive is present in the film-forming
composition in an amount ranging from about 0.01 to about 10
percent by weight based upon the total weight of resin solids
present in the film-forming composition.
54. The multi-layer composite coating of claim 46, wherein the
topcoat film-forming composition further comprises at least one
second water dilutable additive that is different from the first
water dilutable additive, wherein the second water dilutable
additive comprises a reactive functional group-containing
polysiloxane.
55. The multi-layer composite coating of claim 54 wherein the
second water dilutable additive comprising a reactive functional
group-containing polysiloxane comprises a carboxylic acid
functional group-containing polysiloxane.
56. The multi-layer composite coating of claim 54 wherein the
second water dilutable additive comprising a reactive functional
group-containing polysiloxane is present in the film forming
composition in an amount ranging from 0.1 to 10.0 percent by weight
based on the weight of total solids present in the film-forming
composition.
57. The multi-layer composite coating of claim 46, wherein the
resinous binder comprises (1) at least one reactive functional
group-containing polymer and (2) at least one crosslinking agent
having functional groups reactive with the functional groups of the
polymer.
58. The multi-layer composite coating of claim 57, wherein the
polymer (1) is selected from the group consisting of acrylic
polymers, polyester polymers, polyurethane polymers, polyether
polymers, polysiloxane polymers, polyepoxide polymers, copolymers
thereof, and mixtures thereof.
59. The multi-layer composite coating of claim 57, wherein the
polymer (1) contains functional groups selected from the group
consisting of hydroxyl groups, carbamate groups, carboxyl groups,
isocyanate groups, amino groups, amido groups, and combinations
thereof.
60. The multi-layer composite coating of claim 46, wherein the
resinous binder comprises an aqueous dispersion comprising
polymeric microparticles that are adapted to react with a
crosslinking agent.
61. The multi-layer composite coating of claim 60, wherein the
polymeric microparticles are prepared from at least one polymer
having reactive functional groups and at least one crosslinking
agent.
62. The multi-layer composite coating of claim 61, wherein the
polymer comprises a substantially hydrophobic polymer.
63. The multi-layer composite coating of claim 46, wherein the
resinous binder comprises an aqueous dispersion of polymeric
microparticles prepared from (1) one or more reaction products of
ethylenically unsaturated monomers, at least one of which contains
at least one acid functional group, (2) one or more polymers
different from (1) and (3), and (3) one or more crosslinking agents
having functional groups reactive with those of at least one of the
reaction product (1) and the polymer (2).
64. The multi-layer composite coating of claim 63, wherein the
polymer (2) comprises a substantially hydrophobic polymer and the
crosslinking agent (3) comprises a substantially hydrophobic
crosslinking agent.
65. The multi-layer composite coating of claim 46, wherein the
resinous binder comprises an aqueous dispersion of polymeric
microparticles prepared from (A) at least one functional
group-containing reaction product of polymerizable, ethylenically
unsaturated monomers; and (B) at least one reactive
organopolysiloxane.
66. The multi-layer composite coating of claim 65, wherein the
polymeric microparticles are also prepared from (C) at least one
substantially hydrophobic crosslinking agent.
67. The multi-layer composite coating of claim 65, wherein (B)
comprises at least one of the following structural unit:
R.sup.1.sub.nR.sup.2.sub.m- --(--Si--O).sub.(4-n-m)/2 wherein m and
n each represent a positive number fulfilling the requirements of:
0<n<4; 0<m<4; and 2.ltoreq.(m+n)<4; R.sup.1
represents H, OH or monovalent hydrocarbon groups; and R.sup.2
represents a monovalent reactive functional group-containing
organic moiety.
68. The multi-layer composite coating of claim 65, wherein the
reactive organopolysiloxane is substantially hydrophobic.
69. The multi-layer composite coating of claim 46, wherein the
topcoat film-forming composition further comprises at least one
crosslinking agent that is adapted to be at least one of water
soluble and water dispersible.
70. The multi-layer composite coating of claim 69, wherein the
crosslinking agent that is adapted to be at least one of water
soluble and water dispersible is selected from the group consisting
of polyisocyanates, aminoplast resins, and mixtures thereof.
71. The multi-layer composite coating of claim 69, wherein the
crosslinking agent that is adapted to be at least one of water
soluble and water dispersible is present in the film-forming
composition in an amount ranging from 0 to 70 percent by weight
based on total weight of resin solids present in the
composition.
72. The multi-layer composite coating of claim 46, further
comprising an aqueous dispersion of polymeric microparticles
prepared by emulsion polymerization of a monomeric composition
comprising (1) at least 10 percent by weight of one or more vinyl
aromatic compounds; (2) 0 to 10 percent by weight of one or more
carboxylic acid functional polymerizable, ethylenically unsaturated
monomers; (3) 0 to 10 percent by weight of one or more
polymerizable monomers having one or more functional groups which
are capable of reacting to form crosslinks; and (4) one or more
polymerizable ethylenically-unsaturated monomers, where the weight
percentages are based on total weight of monomers present in the
monomeric composition, and wherein each of (1), (2), (3) and (4)
above is different one from the other, and at least one of (3) and
(4) is present in the monomeric composition.
73. The multi-layer composite coating of claim 46, wherein the
topcoat film-forming composition further comprises inorganic
selected from fused silica, amorphous silica, colloidal silica,
alumina, colloidal alumina, titanium dioxide, zirconia, colloidal
zirconia and mixtures thereof.
74. The multi-layer composite coating of claim 73, wherein the
inorganic particles have an average particle size ranging from 1 to
1000 nanometers prior to incorporation into the topcoat
film-forming composition.
75. The multi-layer composite coating of claim 73, wherein the
inorganic particles hvae an average particle size ranging from 1 to
10 microns prior to incorporation into the topcoat film-forming
composition.
76. A method of applying a multi-layer composite coating to a
substrate comprising the following steps: (a) applying to a
substrate a film-forming composition from which a basecoat is
deposited onto the substrate; and (b) applying onto at least a
portion of the basecoat a film-forming composition that is
substantially free of organic solvent from which a topcoat is
deposited over the basecoat, the film-forming composition that is
substantially free of organic solvent comprising: a resinous
binder; and at least one water first dilutable additive comprising
the reaction product of (i) a reactant comprising at least one
isocyanate functional group with (ii) an active hydrogen containing
alkoxypolyalkylene compound.
77. The method of claim 76, wherein the basecoat is deposited from
at least one film-forming composition comprising at least one
pigment.
78. The method of claim 76, wherein the topcoat is transparent.
79. The method of claim 76 wherein the reactant (i) comprises a
polyisocyanate selected from the group consisting of aliphatic
polyisocyanates, cycloaliphatic polyisocyanates, aromatic
polyisocyanates, and mixtures thereof.
80. The method of claim 79, wherein the reactant (i) comprises a
diisocyanate.
81. The method of claim 76, wherein the reactant (ii) comprises an
alkoxyethylene glycol.
82. The method of claim 76, wherein the first water dilutable
additive is present in the film-forming composition in an amount
ranging from about 0.01 to about 10 percent by weight based upon
the total weight of resin solids present in the film-forming
composition.
83. The method of claim 76, wherein the film-forming composition
that is substantially free of organic solvent further comprises at
least one second water dilutable additive that is different from
the first water dilutable additive, wherein the second water
dilutable additive comprises a reactive functional group-containing
polysiloxane.
84. The method of claim 83, wherein the second water dilutable
additive comprising a reactive functional group-containing
polysiloxane comprises a carboxylic acid functional
group-containing polysiloxane.
85. The method of claim 83 wherein the second water dilutable
additive comprising a reactive functional group-containing
polysiloxane is present in the film forming composition in an
amount ranging from 0.1 to 10.0 weight percent based on the total
weight of resin solids present in the film-forming composition.
86. The method of claim 76, wherein the resinous binder comprises
(1) at least one reactive functional group-containing polymer and
(2) at least one crosslinking agent having functional groups
reactive with the functional groups of the polymer.
87. The method of claim 86, wherein the polymer (1) is selected
from the group consisting of acrylic polymers, polyester polymers,
polyurethane polymers, polyether polymers, polysiloxane polymers,
polyepoxide polymers, copolymers thereof, and mixtures thereof.
88. The method of claim 87, wherein the polymer (1) contains
functional groups selected from the group consisting of hydroxyl
groups, carbamate groups, carboxyl groups, isocyanate groups, amino
groups, amido groups, and combinations thereof.
89. The method of claim 76, wherein the resinous binder comprises
an aqueous dispersion comprising polymeric microparticles that are
adapted to react with a crosslinking agent.
90. The method of claim 89, wherein the polymeric microparticles
are prepared from at least one polymer-having reactive functional
groups and at least one crosslinking agent.
91. The method of claim 90, wherein the polymer comprises a
substantially hydrophobic polymer.
92. The method of claim 76, wherein the resinous binder comprises
an aqueous dispersion of polymeric microparticles prepared from (1)
one or more reaction products of ethylenically unsaturated
monomers, at least one of which contains at least one acid
functional group, (2) one or more polymers different from (1) and
(3), and (3) one or more crosslinking agents having functional
groups reactive with those of at least one of the reaction product
(1) and the polymer (2).
93. The method of claim 92, wherein the polymer (2) comprises a
substantially hydrophobic polymer and the crosslinking agent (3)
comprises a substantially hydrophobic crosslinking agent.
94. The method of claim 76, wherein the resinous binder comprises
an aqueous dispersion of polymeric microparticles prepared from (A)
at least one functional group-containing reaction product of
polymerizable, ethylenically unsaturated monomers; and (B) at least
one reactive organopolysiloxane.
95. The method of claim 94, wherein the polymeric microparticles
are also prepared from (C) at least one substantially hydrophobic
crosslinking agent.
96. The method of claim 94, wherein (B) comprises at least one of
the following structural unit:
R.sup.1.sub.nR.sup.2.sub.m--(--Si--O).sub.(4-n- -m)/2 wherein m and
n each represent a positive number fulfilling the requirements of:
0<n<4; 0<m<4; and 2.ltoreq.(m+n)<4; R.sup.1
represents H, OH or monovalent hydrocarbon groups; and R.sup.2
represents a monovalent reactive functional group-containing
organic moiety.
97. The method of claim 94, wherein the reactive organopolysiloxane
is substantially hydrophobic.
98. The method of claim 76, wherein the film-forming composition
that is substantially free of organic solvent further comprises at
least one crosslinking agent that is adapted to be at least one of
water soluble and water dispersible.
99. The method of claim 98, wherein the crosslinking agent that is
adapted to be at least one of water soluble and water dispersible
is selected from the group, consisting of hydrophilically modified
polyisocyanates, aminoplast resins, and mixtures thereof.
100. The method of claim 98, wherein the crosslinking agent that is
adapted to be at least one of water soluble and water dispersible
is present in the film-forming composition that is
substantially-free of organic solvent in an amount ranging from 0
to 70 percent by weight based on total weight of resin solids
present in the composition.
101. The method of claim 76, wherein the film-forming composition
that is substantially free of organic solvent further comprises an
aqueous dispersion of polymeric microparticles prepared by emulsion
polymerization of a monomeric composition comprising (1) at least
10 percent by weight of one or more vinyl aromatic compounds; (2) 0
to 10 percent by weight of one or more carboxylic acid functional
polymerizable, ethylenically unsaturated monomers; (3) 0 to 10
percent by weight of one or more polymerizable monomers having one
or more functional groups which are capable of reacting to form
crosslinks; and (4) one or more polymerizable ethylenically
unsaturated monomers, where the weight percentages are based on
total weight of monomers present in the monomeric composition, and
wherein each of (1), (2), (3) and (4) above is different one from
the other, and at least one of (3) and (4) is present in the
monomeric composition.
102. The method of claim 76, wherein the film-forming composition
that is substantially free of organic solvent further comprises
inorganic particles selected from fused silica, amorphous silica,
colloidal silica, alumina, colloidal alumina, titanium dioxide,
zirconia, colloidal zirconia and mixtures thereof.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is related to U.S. patent application Ser.
No. ______, entitled, "Organic Solvent-Free Film-Forming
Compositions, Multilayer Composite Coatings, and Related Methods",
filed concurrently herewith.
FIELD OF THE INVENTION
[0002] The present invention relates to substantially solvent free
film-forming compositions, multi-layer composite coatings
comprising such film-forming compositions and methods of applying
such multi-component composite coatings to a substrate.
BACKGROUND INFORMATION
[0003] Color-plus-clear coating systems formed from the application
of a transparent topcoat over a colored basecoat have become
increasingly popular in the coatings industry, particularly for use
in coating automobiles. The most economically attractive
color-plus-clear systems are those in which the clear coat
composition can be applied directly over the uncured colored
basecoat. The process of applying one layer of a coating before the
previous layer is cured, then simultaneously curing both layers, is
referred to as a wet-on-wet ("WOW") application. Color-plus-clear
coating systems suitable for WOW application provide a substantial
energy cost savings advantage.
[0004] Over the past decade, there has been an effort to reduce
atmospheric pollution caused by volatile solvents that are emitted
during the painting process. It is, however, often difficult to
achieve high quality, smooth coating finishes, particularly clear
coating finishes, such as are required in the automotive industry,
without including organic solvents which contribute greatly to flow
and leveling of a coating. In addition to achieving near-flawless
appearance, automotive coatings must be durable and chip resistant,
yet economical and easy to apply.
[0005] The use of powder coatings to eliminate the emission of
volatile solvents during the painting process has become
increasingly attractive. Powder coatings have become quite popular
for use in coatings for automotive components, for example, wheels,
axle parts, seat frames and the like. Use of powder coatings for
clear coats in color-plus-clear systems, however, is somewhat less
prevalent for several reasons. First, powder coatings require a
different application technology than conventional liquid coating
compositions and, thus, require expensive modifications to
application lines. Also, most automotive topcoat compositions
typically are cured at temperatures below 140.degree. C. By
contrast, most powder coating formulations require a much higher
curing temperature. Further, many powder coating compositions tend
to yellow more readily than conventional liquid coating
compositions, and generally result in coatings having a high cured
film thickness, often ranging from 60 to 70 microns.
[0006] Powder coatings in slurry form for automotive coatings can
overcome many of the disadvantages of dry powder coatings, however,
powder slurry compositions can be unstable and settle upon storage
at temperatures above 20.degree. C. Further, WOW application of
powder slurry clear coating compositions over conventional
basecoats can result in mud-cracking of the system upon curing. See
Aktueller Status bei der Pulverlackentwickluna fur die
Automobilindustrie am Beispiel fuller und Klarlack, presented by
Dr. W. Kries at the 1st International Conference of Car-Body Powder
Coatings, Berlin, Germany, Jun. 22-23, 1998, reprinted in Focus on
Powder Coatings, The Royal Society of Chemistry, Sep. 2-8,
1998.
[0007] Some aqueous dispersions are known to form powder coatings
at ambient temperatures. Although applied as conventional
waterborne coating compositions, these dispersions form powder
coatings at ambient temperature that require a ramped bake prior to
undergoing conventional curing conditions in order to effect a
coalesced and continuous film on the substrate surface. Also, many
waterborne coating compositions contain a substantial amount of
organic solvent to provide flow and coalescence of the applied
coating.
[0008] The automotive industry would derive a significant economic
benefit from an essentially organic solvent-free clear coating
composition which meets the stringent automotive appearance and
performance requirements, while maintaining ease of application and
performance properties, such as sag and crater resistance. Also, it
would be advantageous to provide an organic solvent-free clear coat
composition which can be applied by conventional application means
over an uncured pigmented base coating composition (i.e., via WOW
application) to form a generally continuous film at ambient
temperature which provides a cured film free of mud-cracking.
SUMMARY OF THE INVENTION
[0009] The present invention is directed to film-forming
compositions that are substantially free of organic solvent. The
film-forming compositions comprise (a) a resinous binder; and (b)
at least one water dilutable additive comprising the reaction
product of (i) a reactant comprising at least one isocyanate
functional group with (ii) an active hydrogen containing
alkoxypolyalkylene compound. The present invention is also directed
to film-forming compositions that are substantially free of organic
solvent, which comprise (a) an aqueous dispersion comprising
polymeric microparticles that are adapted to react with a
crosslinking agent, (b) at least one water dilutable additive
comprising the reaction product of (i) a reactant comprising at
least one isocyanate functional group with (ii) an active hydrogen
containing alkoxypolyalkylene compound, and (c) at least one water
dilutable additive comprising a reactive carboxylic acid functional
group-containing polysiloxane.
[0010] The present invention is also directed to multi-layer
composite coatings. The multi-layer composite coatings of the
present invention comprise a basecoat deposited from at least one
basecoat film-forming composition and a topcoat composition applied
over at least a portion of the basecoat. The topcoat of the
multi-layer composite coatings of the present invention is
deposited from at least one topcoat film-forming composition that
is substantially free of organic solvent, and which comprises (a) a
resinous binder; and (b) at least one water dilutable additive
comprising the reaction product of (i) a reactant comprising at
least one isocyanate functional group with (ii) an active hydrogen
containing alkoxypolyalkylene compound.
[0011] The present invention is also directed to methods of
applying a multi-component composite coating to a substrate. These
methods of the present invention comprise the steps of applying to
a substrate a film-forming composition from which a basecoat is
deposited onto at least a portion of the substrate, and applying
onto at least a portion of the basecoat a film-forming composition
that is substantially free of organic solvent from which a topcoat
is deposited over the basecoat. In accordance with these methods of
the present invention, the film-forming composition that is
substantially free of organic solvent comprises any of the
film-forming compositions of the present invention.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0012] For purposes of the following detailed description, it is to
be understood that the invention may assume various alternative
variations and step sequences, except where expressly specified to
the contrary. It is also to be understood that the specific devices
and processes are simply exemplary embodiments of the invention.
Hence, specific dimensions and other physical characteristics
related to the embodiments disclosed herein are not to be
considered as limiting. Moreover, other than in any operating
examples, or where otherwise indicated, all numbers expressing, for
example, quantities of ingredients used in the specification and
claims are to be understood as being modified in all instances by
the term "about." Accordingly, unless indicated to the contrary,
the numerical parameters set forth in the following specification
and attached claims are approximations that may vary depending upon
the desired properties to be obtained by the present invention. At
the very least, and not as an attempt to limit the application of
the doctrine of equivalents to the scope of the claims, each
numerical parameter should at least be construed in light of the
number of reported significant digits and by applying ordinary
rounding techniques.
[0013] Notwithstanding that the numerical ranges and parameters
setting forth the broad scope of the invention are approximations,
the numerical values set forth in the specific examples are
reported as precisely as possible. Any numerical value, however,
inherently contains certain errors necessarily resulting from the
standard deviation found in their respective testing
measurements.
[0014] It should also be understood that any numerical range
recited herein is intended to include all sub-ranges subsumed
therein. For example, a range of "1 to 10" is intended to include
all sub-ranges between (and including) the recited minimum value of
1 and the recited maximum value of 10, that is, having a minimum
value equal to or greater than 1 and a maximum value of equal to or
less than 10.
[0015] In certain embodiments of the present invention, the
film-forming compositions of the present invention are
substantially free of organic solvent and comprise: a resinous
binder; and at least one first water dilutable additive comprising
the reaction product of (i) a reactant comprising at least one
isocyanate functional group with (ii) an active hydrogen containing
alkoxypolyalkylene compound. As used herein, the term
"substantially free of organic solvent" means that the amount of
organic solvent present in the composition is less than 10 weight
percent based on total weight of the film-forming composition. In
certain particular embodiments, the amount of organic solvent in
the composition is less than 5 weight percent, or less than 2
weight percent, based on total weight of the film-forming
composition. It should be understood, however, that a small amount
of organic solvent can be present in the composition, for example
to improve flow and leveling of the applied coating or to decrease
viscosity as needed.
[0016] As noted above, the film-forming compositions of the present
invention include at least one first water dilutable additive
comprising the reaction product of (i) a reactant comprising at
least one isocyanate functional group with (ii) an active hydrogen
containing alkoxypolyalkylene compound. As used herein, the term
"water dilutable" means that the additive is or has been adapted to
be water soluble or water dispersible.
[0017] The isocyanates that are useful as reactant (i) in preparing
the first water dilutable additive of the film-forming compositions
of the present invention include both monoisocyanates or
polyisocyanates, or a mixture thereof. They can be aliphatic or
aromatic isocyanates, such as any of those discussed below.
[0018] In addition, the polyisocyanates may be prepolymers derived
from polyols such as polyether polyols or polyester polyols,
including polyols that are reacted with excess polyisocyanates to
form isocyanate-terminated prepolymers. Examples of the suitable
isocyanate prepolymers are described in U.S. Pat. No. 3,799,854,
column 2, lines 22 to 53, which is herein incorporated by
reference.
[0019] In certain particular embodiments of the present invention,
the isocyanate that is used as reactant (i) in preparing the first
water dilutable additive of the film-forming compositions of the
present invention comprises isophorone diisocyanate.
[0020] The active hydrogen containing alkoxypolyalkylenes which are
useful as reactant (ii) in preparing the first water dilutable
additive of the film-forming compositions of the present invention
include alkoxyethylene glycols, such as, for example,
methoxypolyethylene glycol and butoxypolyethylene glycol. Also
suitable for use as reactant (ii) in preparing the first water
dilutable additive of the film-forming compositions of the present
invention are polyalkoxyalkylene amines, including polyoxyalkylene
monoamines, and polyoxyalkylene polyamines, for example,
polyoxyalkylene diamines. Specific non-limiting examples of
suitable polyoxyalkylene polyamines include polyoxypropylene
diamines commercially available under the tradenames JEFFAMINE.RTM.
D-2000 and JEFFAMINE.RTM. D-400 from Huntsman Corporation of
Houston, Tex. Mixed polyoxyalkylene polyamines, that is, those in
which the oxyalkylene group can be selected from more than one
moiety, also can be used as reactant (ii).
[0021] According to certain embodiments of the present invention,
the first water dilutable additive is present in the film forming
composition in an amount ranging from 0.01 up to 10 percent by
weight, or in an amount ranging from 1 up to 8 percent by weight,
or, in yet other embodiments, in an amount ranging from 2 up to 7
percent by weight based on total-weight of resin solids present in
the film-forming composition. The amount of the first water
dilutable additive present in the film forming compositions can
range between any combination of the recited values, inclusive of
the recited values. It will be understood by those skilled in the
art that the amount of the first water dilutable additive present
in the film forming composition is determined by the properties
desired to be incorporated into the film-forming composition.
[0022] In certain embodiments of the present invention, the
film-forming composition may include, in addition to or in lieu of
the first water dilutable additive, at least one second water
dilutable additive which is different from the first water
dilutable additive and which comprises a reactive functional
group-containing polysiloxane, such as a hydroxyl, carboxylic acid
and/or amine functional group-containing polysiloxane.
[0023] In accordance with certain embodiments of the present
invention, the at least one second water dilutable additive may
comprise a carboxylic acid functional group-containing
polysiloxane, such as a polysiloxane having the following general
structure (I) or (II): 1
[0024] where m is at least 1; m' is 0 to 50; n is 0 to 50; R is
selected from the group consisting of OH and monovalent hydrocarbon
groups connected to the silicon atoms; R.sup.a has the following
structure (III):
R.sub.1--O--X (III)
[0025] wherein R.sub.1 is alkylene, oxyalkylene or alkylene aryl;
and at least one X contains one or more COOH functional groups.
[0026] The acid functional polysiloxane can be prepared, for
example, by reacting (a) a polysiloxane polyol; and (b) at least
one carboxylic acid functional material or anhydride. The resulting
acid functional polyol is further neutralized with, for example,
amine, to render the reaction product water dilutable. In
accordance with certain embodiments of the present invention, the
carboxylic acid functional group-containing polysiloxane is the
reaction product of the following reactants: (i) a polysiloxane
polyol of the following general formula (IV) or (V): 2
[0027] where m is at least 1; m' is 0 to 50; n is 0 to 50; R is
selected from the group consisting of H, OH and monovalent
hydrocarbon groups connected to the silicon atoms; and R.sup.b has
the following structure (VI):
R.sub.1--O--Y (VI)
[0028] wherein R.sub.1 is alkylene, oxyalkylene or alkylene aryl;
and the moiety Y is H, mono-hydroxy-substituted alkyl or oxyalkyl,
or has the structure of CH.sub.2C(R.sub.2).sub.a(R.sub.3).sub.b
wherein R.sub.2 is CH.sub.2OH, R.sub.3 is an alkyl group containing
from 1 to 4 carbon atoms, a is 2 or 3, and b is 0 or 1; and (ii) at
least one polycarboxylic acid or anhydride. The resulting acid
functional polyol is further neutralized with, for example, amine,
to form the water dilutable additive (c).
[0029] Examples of anhydrides suitable for use in the present
invention as reactant (ii) immediately above include
hexahydrophthalic anhydride, methyl hexahydrophthalic anhydride,
phthalic anhydride, trimellitic anhydride, succinic anhydride,
chlorendic anhydride, alkenyl succinic anhydride and substituted
alkenyl succinic anhydride, and mixtures thereof.
[0030] According to certain embodiments of the present invention,
the second water dilutable additive can be present in the film
forming compositions in an amount ranging from 0.1 up to 10.0
weight percent based on total weight resin solids present in the
film-forming composition, or in an amount ranging from 0.1 up to
5.0 weight percent or, in yet other embodiments, in an amount
ranging from 0.1 to 1.0 weight percent based on the weight of total
solids present in the film-forming composition.
[0031] As previously mentioned, the film-forming compositions of
the present invention comprise, in addition to the first water
dilutable additive and/or the second water dilutable additive, a
resinous binder. In certain embodiments of the present invention,
the resinous binder present in the film-forming composition
comprises (1) at least one reactive functional group-containing
polymer, and (2) at least one crosslinking agent having functional
groups reactive with the functional groups of the polymer. The
polymer (1) can comprise any of a variety of reactive
group-containing polymers well known in the surface coatings art
provided the polymer is sufficiently dispersible in aqueous media.
Suitable non-limiting examples can include, without limitation,
acrylic polymers, polyester polymers, polyurethane polymers,
polyether polymers, polysiloxane polymers, polyepoxide polymers,
copolymers thereof, and mixtures thereof. Also, the polymer (1) may
comprise a variety of reactive functional groups such as, for
example, functional groups selected from at least one of hydroxyl
groups, carboxyl groups, amino groups, amido groups, carbamate
groups, isocyanate groups, and combinations thereof.
[0032] Suitable hydroxyl group-containing polymers include, for
example, acrylic polyols, polyester polyols, polyurethane polyols,
polyether polyols, and mixtures thereof. In certain embodiments of
the present invention, the polymer (1) comprises an acrylic polyol
having an hydroxyl equivalent weight ranging from 1000 to 100 grams
per solid equivalent, or, in certain embodiments, 500 to 150 grams
per solid equivalent.
[0033] In the embodiments of the present invention wherein the
polymer (1) is an acrylic polymer, suitable hydroxyl group and/or
carboxyl group-containing acrylic polymers can be prepared from
polymerizable ethylenically unsaturated monomers and are often
copolymers of (meth)acrylic acid and/or hydroxyalkyl esters of
(meth)acrylic acid with one or more other polymerizable
ethylenically unsaturated monomers, such as alkyl esters of
(meth)acrylic acid, including methyl(meth)acrylate, ethyl
(meth)acrylate, butyl(meth)acrylate and 2-ethyl hexylacrylate, and
vinyl aromatic compounds, such as styrene, alpha-methyl styrene,
and vinyl toluene. As used herein, "(meth)acrylic" and terms
derived therefrom are intended to include both acrylic and
methacrylic.
[0034] In the embodiments of the present invention wherein the
polymer (1) is an acrylic polymer, the polymer may, for example, be
prepared from ethylenically unsaturated, beta-hydroxy ester
functional monomers. Such monomers may, for example, be derived
from the reaction of an ethylenically unsaturated acid functional
monomer, such as a monocarboxylic acid, e.g., acrylic acid, and an
epoxy compound which does not participate in the free radical
initiated polymerization with such unsaturated acid functional
monomer. Non-limiting examples of such epoxy compounds include
glycidyl ethers and esters. Suitable glycidyl ethers include, for
example, glycidyl ethers of alcohols and phenols, such as butyl
glycidyl ether, octyl glycidyl ether, phenyl glycidyl ether, and
the like. Suitable glycidyl esters include, for example, those
commercially available from Shell Chemical Company under the
tradename CARDURA E; and from Exxon Chemical Company under the
tradename GLYDEXX-10. Alternatively, the beta-hydroxy ester
functional monomers can be prepared from an ethylenically
unsaturated, epoxy functional monomer, such as, for example,
glycidyl(meth)acrylate and allyl glycidyl ether, and a saturated
carboxylic acid, such as, for example, a saturated monocarboxylic
acid, such as, for example, isostearic acid.
[0035] In the embodiments of the present invention wherein the
polymer (1) is an acrylic polymer, epoxy functional groups can be
incorporated into the polymer prepared from polymerizable
ethylenically unsaturated monomers by copolymerizing oxirane
group-containing monomers, such as, for example,
glycidyl(meth)acrylate and allyl glycidyl ether, with other
polymerizable ethylenically unsaturated monomers, such as those
described above. Preparation of such epoxy functional acrylic
polymers is described in detail in U.S. Pat. No. 4,001,156 at
columns 3 to 6, which is incorporated herein by reference.
[0036] In the embodiments of the present invention wherein the
polymer (1) is an acrylic polymer, carbamate functional groups may
be incorporated into the acrylic polymer prepared from
polymerizable ethylenically unsaturated monomers by copolymerizing,
for example, the above-described ethylenically unsaturated
monomers, with a carbamate functional vinyl monomer such as, for
example, a carbamate functional alkyl ester of methacrylic acid.
Useful carbamate functional alkyl esters can be prepared, for
example, by reacting a hydroxyalkyl carbamate, such as, for
example, the reaction product of ammonia and ethylene carbonate or
propylene carbonate, with methacrylic anhydride. Other useful
carbamate functional vinyl monomers include, for example, the
reaction product of hydroxyethyl methacrylate, isophorone
diisocyanate, and hydroxypropyl carbamate; or the reaction product
of hydroxypropyl methacrylate, isophorone diisocyanate, and
methanol. Still other carbamate functional vinyl monomers may be
used, such as the reaction product of isocyanic acid (HNCO) with a
hydroxyl functional acrylic or methacrylic monomer such as
hydroxyethyl acrylate, and those described in U.S. Pat. No.
3,479,328, incorporated herein by reference. Carbamate functional
groups can also be incorporated into the acrylic polymer by
reacting a hydroxyl functional acrylic polymer with a low molecular
weight alkyl carbamate such as methyl carbamate. In addition,
pendant carbamate groups can be incorporated into the acrylic
polymer by a "transcarbamoylation" reaction in which a hydroxyl
functional acrylic polymer is reacted with a low molecular weight
carbamate derived from an alcohol or a glycol ether. The carbamate
groups exchange with the hydroxyl groups yielding the carbamate
functional acrylic polymer and the original alcohol or glycol
ether. Also, hydroxyl functional acrylic polymers can be reacted
with isocyanic acid to provide pendent carbamate groups. The
production of isocyanic acid is disclosed in U.S. Pat. No.
4,364,913, which is incorporated herein by reference. Likewise,
hydroxyl functional acrylic polymers can be reacted with urea to
provide pendent carbamate groups.
[0037] The polymers prepared from polymerizable ethylenically
unsaturated monomers may, for example, be prepared by solution
polymerization techniques, which are well-known to those skilled in
the art, in the presence of suitable catalysts such as organic
peroxides or azo compounds, for example, benzoyl peroxide or
N,N-azobis(isobutylronitrile)- . The polymerization can be carried
out in an organic solution in which the monomers are soluble by
techniques conventional in the art. Alternatively, these polymers
can be prepared by aqueous emulsion or dispersion polymerization
techniques that are well-known in the art. The ratio of reactants
and reaction conditions are selected to result in an acrylic
polymer with the desired pendent functionality.
[0038] As mentioned earlier, polyester polymers are also useful as
polymer (1) in the film-forming compositions of the present
invention. In these embodiments, useful polyester polymers often
include the condensation products of polyhydric alcohols and
polycarboxylic acids. Suitable polyhydric alcohols can include, for
example, ethylene glycol, neopentyl glycol, trimethylol propane,
and pentaerythritol. Suitable polycarboxylic acids can include, for
example, adipic acid, 1,4-cyclohexyl dicarboxylic acid, and
hexahydrophthalic acid. Besides the polycarboxylic acids mentioned
above, functional equivalents of the acids such as anhydrides where
they exist or lower alkyl esters of the acids such as the methyl
esters can be used. Also, small amounts of monocarboxylic acids
such as stearic acid can be used. The ratio of reactants and
reaction conditions are selected to result in a polyester polymer
with the desired pendent functionality, i.e., carboxyl or hydroxyl
functionality.
[0039] For example, hydroxyl group-containing polyesters can be
prepared by reacting an anhydride of a dicarboxylic acid such as
hexahydrophthalic anhydride with a diol such as neopentyl glycol in
a 1:2 molar ratio. Where it is desired to enhance air-drying,
suitable drying oil fatty acids may be used and include those
derived from linseed oil, soya bean oil, tall oil, dehydrated
castor oil, or tung oil.
[0040] Carbamate functional polyesters can be prepared by first
forming a hydroxyalkyl carbamate that can be reacted with the
polyacids and polyols used in forming the polyester. Alternatively,
terminal carbamate functional groups can be incorporated into the
polyester by reacting isocyanic acid with a hydroxy functional
polyester. Also, carbamate functionality can be incorporated into
the polyester by reacting a hydroxyl polyester with a urea.
Additionally, carbamate groups can be incorporated into the
polyester by a transcarbamoylation reaction. Preparation of
suitable carbamate functional group-containing polyesters include,
for example, those described in U.S. Pat. No. 5,593,733 at column
2, line 40 to column 4, line 9, incorporated herein by
reference.
[0041] As mentioned above, polyurethane polymers containing
terminal isocyanate or hydroxyl groups also can be used as the
polymer (1) in the film-forming compositions of the present
invention. In these embodiments, the polyurethane polyols or
NCO-terminated polyurethanes that can be used include, for example,
those prepared by reacting polyols including polymeric polyols with
polyisocyanates. Polyureas containing terminal isocyanate or
primary and/or secondary amine groups that also can be used are
those prepared by reacting polyamines including polymeric
polyamines with polyisocyanates. The hydroxyl/isocyanate or
amine/isocyanate equivalent ratio is adjusted and reaction
conditions are selected to obtain the desired terminal groups.
Examples of suitable polyisocyanates include, for example, those
described in U.S. Pat. No. 4,046,729 at column 5, line 26 to column
6, line 28, incorporated herein by reference. Examples of suitable
polyols include, for example, those described in U.S. Pat. No.
4,046,729 at column 7, line 52 to column 10, line 35, incorporated
herein by reference. Examples of suitable polyamines include, for
example, those described in U.S. Pat. No. 4,046,729 at column 6,
line 61 to column 7, line 32 and in U.S. Pat. No. 3,799,854 at
column 3, lines 13 to 50, both incorporated herein by
reference.
[0042] In the embodiments of the present invention wherein the
polymer (1) is a polyurethane polymer, carbamate functional groups
may be incorporated into the polyurethane polymer by reacting a
polyisocyanate with a polyester having hydroxyl functionality and
containing pendent carbamate groups. Alternatively, the
polyurethane can be prepared by reacting a polyisocyanate with a
polyester polyol and a hydroxyalkyl carbamate or isocyanic acid as
separate reactants. Examples of suitable polyisocyanates include
aromatic isocyanates, such as 4,4'-diphenylmethane diisocyanate,
1,3-phenylene diisocyanate and toluene diisocyanate, and aliphatic
polyisocyanates, such as, for example, 1,4-tetramethylene
diisocyanate and 1,6-hexamethylene diisocyanate. Cycloaliphatic
diisocyanates, such as, for example, 1,4-cyclohexyl diisocyanate
and isophorone diisocyanate also can be employed.
[0043] Examples of suitable polyether polyols include polyalkylene
ether polyols such as those having the following structural formula
(VII): 3
[0044] wherein the substituent R is hydrogen or a lower alkyl group
containing from 1 to 5 carbon atoms including mixed substituents,
and n has a value typically ranging from 2 to 6 and m has a value
ranging from 8 to 100 or higher. Exemplary polyalkylene ether
polyols include, for example, poly(oxytetramethylene)glycols,
poly(oxytetraethylene)glycols, poly(oxy-1,2-propylene)glycols, and
poly(oxy-1,2-butylene)glycols.
[0045] Also useful are polyether polyols formed from oxyalkylation
of various polyols, for example, glycols such as ethylene glycol,
1,6-hexanediol, Bisphenol A, and the like, or other higher polyols
such as trimethylolpropane, pentaerythritol, and the like. Polyols
of higher functionality can be made, for instance, by oxyalkylation
of compounds such as sucrose or sorbitol. One commonly utilized
oxyalkylation method is reaction of a polyol with an alkylene
oxide, for example, propylene or ethylene oxide, in the presence of
an acidic or basic catalyst. Specific examples of polyethers
include those sold under the names TERATHANE and TERACOL, available
from E. I. Du Pont de Nemours and Company, Inc.
[0046] Generally, the polymers having reactive functional groups
which are useful in the film-forming compositions of the present
invention can have a weight average molecular weight (Mw) typically
ranging from 1-000 to 20,000, or from 1500 to 15,000 or from 2000
to 12,000 as determined by gel permeation chromatography using a
polystyrene standard.
[0047] In certain embodiments of the present invention, the
resinous binder present in the film-forming compositions of the
present invention comprises an aqueous dispersion comprising
polymeric microparticles that are adapted to react with a
crosslinking agent. As used herein, the term "dispersion" means
that the microparticles are capable of being distributed throughout
water as finely divided particles, such as a latex. See Hawley's
Condensed Chemical Dictionary, (12th Ed. 1993) at page 435, which
is hereby incorporated by reference. The uniformity of the
dispersion can be increased by the addition of wetting, dispersing
or emulsifying agents (surfactants). In certain embodiments of the
invention, the amount of the dispersion resin solids present in the
film-forming composition may be forming at least 20 weight percent,
or, in some embodiments, from at least 30 weight percent, or, in
yet other embodiments, from at least 40 weight percent based on the
total resin solids weight of the film-forming composition. In
certain embodiments of the invention, the amount of the dispersion
resin solids present in the film-forming composition also can be no
more than 90 weight percent, or, in some embodiments, no more than
85 weight percent, or, in yet other embodiments, no more than 80
weight percent based on the total resin solids weight of the
film-forming composition. The amount of the dispersion of polymeric
microparticles present in the film-forming composition can range
between any combination of these values inclusive of the recited
values. The solids content is determined by heating a sample of the
composition to 105.degree. to 110.degree. C. for 1-2 hours to drive
off the volatile material, and subsequently measuring relative
weight loss.
[0048] In certain embodiments of the present invention, the
resinous binder comprises an aqueous dispersion of polymeric
microparticles prepared from (i) at least one polymer having
reactive functional groups, typically a substantially hydrophobic
polymer; and (ii) at least one crosslinking agent, typically a
substantially hydrophobic crosslinking agent, containing functional
groups that are reactive with the functional groups of the polymer.
Suitable substantially hydrophobic polymers can be prepared by
polymerizing one or more ethylenically unsaturated carboxylic acid
functional group-containing monomers and one or more other
ethylenically unsaturated monomers free of acid functionality,
e.g., an ethylenically unsaturated monomer having hydroxyl and/or
carbamate functional groups. Suitable substantially hydrophobic
crosslinking agents can include, for example, polyisocyanates,
blocked polyisocyanates and aminoplast resins. Suitable aqueous
dispersions of polymeric microparticles and the preparation thereof
include those described in detail in U.S. Pat. No. 6,462,139 at
column 4, line 17 to column 11, line 49, which is incorporated
herein by reference.
[0049] As used herein, the term "substantially hydrophobic" means
that the hydrophobic component is essentially not compatible with,
does not have an affinity for and/or is not capable of dissolving
in water using conventional mixing means. That is, upon mixing a
sample of the hydrophobic component with an organic component and
water, a majority of the hydrophobic component is in the organic
phase and a separate aqueous phase is observed. See Hawley's
Condensed Chemical Dictionary, (12th ed. 1993) at page 618.
[0050] In certain embodiments of the present invention, the
resinous binder comprises an aqueous dispersion of polymeric
microparticles prepared from (1) one or more reaction products of
ethylenically unsaturated monomers, at least one of which contains
at least one acid functional group, (2) one or more polymers
different from (1) and (3), typically containing reactive
functional groups, which are typically substantially hydrophobic
polymers, and (3) one or more crosslinking agents, typically
substantially hydrophobic crosslinking agents, having functional
groups reactive with those of the reaction product (1) and/or the
polymer (2). The polymer (2) can be any of the well-known polymers
such as acrylic polymers, polyester polymers, alkyd polymers,
polyurethane polymers, polyether polymers, polyurea polymers,
polyamide polymers, polycarbonate polymers, copolymers thereof and
mixtures thereof. Suitable substantially hydrophobic crosslinking
agents include, for example, those identified above. Suitable
aqueous dispersions of polymeric microparticles and the preparation
thereof include those described in detail in U.S. Pat. No.
6,329,060 at column 4, line 27 to column 17, line 6, which is
incorporated herein by reference.
[0051] In certain embodiments of the present invention, the
resinous binder comprises an aqueous dispersion of polymeric
microparticles prepared from components (A) at least one functional
group-containing reaction product of polymerizable, ethylenically
unsaturated monomers; and (B) at least one reactive
organopolysiloxane. The components from which the polymeric
microparticles can be prepared may further include (C) at least one
substantially hydrophobic crosslinking agent. The reactive
organopolysiloxane (B) typically comprises at least one of the
following structural units (VIII):
R.sup.1.sub.nR.sup.2.sub.m--(--Si--O).sub.(4-n-m)/2 (VIII)
[0052] where m and n each represent a positive number fulfilling
the requirements of: 0<n<4; 0<m<4; and
2.ltoreq.(m+n)<4; R.sup.1 represents H, OH or monovalent
hydrocarbon groups; and R.sup.2 represents a monovalent reactive
functional group-containing organic moiety. In certain embodiments
of the present invention, R.sup.2 represents a reactive
group-containing moiety selected from at least one of hydroxyl,
carboxylic acid, isocyanate and blocked isocyanate, primary amine,
secondary amine, amide, carbamate, urea, urethane, alkoxysilane,
vinyl and epoxy functional groups. Suitable aqueous dispersions of
polymeric microparticles and the preparation thereof include those
described in detail in U.S. Pat. No. 6,387,997 at column 3, line 47
to column 14, line 54, which is incorporated herein by
reference.
[0053] In certain embodiments of the present invention, the
film-forming composition may also comprise one or more crosslinking
agents that are adapted to react with the functional groups of the
polymer and/or polymeric microparticles and/or other components in
the composition to provide curing, if desired, for the film-forming
composition. Non-limiting examples of suitable crosslinking agents
include any of the amihoplasts and polyisocyanates generally known
in the art of surface coatings, provided that the crosslinking
agent(s) are adapted to be water soluble or water dispersible as
described below, and polyacids, polyanhydrides and mixtures
thereof. When used, this additional crosslinking agent or mixture
of crosslinking agents is dependent upon the functionality
associated with the polymer and/or polymeric microparticles present
in the composition, such as hydroxyl and/or carbamate
functionality. When, for example, the functionality is hydroxyl,
the crosslinking agent may comprise an aminoplast or polyisocyanate
crosslinking agent.
[0054] Examples of suitable aminoplast resins include those
containing methylol or similar alkylol groups, a portion of which
have been etherified by reaction with a lower alcohol, such as
methanol, to provide a water soluble/dispersible aminoplast resin.
One appropriate aminoplast resin is the partially methylated
aminoplast resin, CYMEL 385, which is commercially available from
Cytec Industries, Inc. An example of a suitable blocked isocyanate
which is water soluble/dispersible is dimethylpyrazole blocked
hexamethylene diisocyanate trimer commercially available as BI 7986
from Baxenden Chemicals, Ltd. in Lancashire, England.
[0055] Polyacid crosslinking materials suitable for use as a
crosslinking agent in the present invention include, for example,
those that on average generally contain greater than one acid group
per molecule, sometimes three or more and sometimes four or more,
such acid groups being reactive with epoxy functional film-forming
polymers. Polyacid crosslinking materials may have di-, tri- or
higher functionalities. Suitable polyacid crosslinking materials
which can be used include, for example, carboxylic acid
group-containing oligomers, polymers and compounds, such as acrylic
polymers, polyesters, and polyurethanes and compounds having
phosphorus-based acid groups.
[0056] Examples of suitable polyacid crosslinking agents include,
for example, ester group-containing oligomers and compounds
including half-esters formed from reacting polyols and cyclic
1,2-acid anhydrides or acid functional polyesters derived from
polyols and polyacids or anhydrides. These half-esters are of
relatively low molecular weight and are quite reactive with epoxy
functionality. Suitable ester group-containing oligomers include
those described in U.S. Pat. No. 4,764,430, column 4, line 26 to
column 5, line 68, which is hereby incorporated by reference.
[0057] Other useful crosslinking agents include acid-functional
acrylic crosslinkers made by copolymerizing methacrylic acid and/or
acrylic acid monomers with other ethylenically unsaturated
copolymerizable monomers as the polyacid crosslinking material.
Alternatively, acid-functional acrylics can be prepared from
hydroxy-functional acrylics reacted with cyclic anhydrides.
[0058] In accordance with certain embodiments of the present
invention, the crosslinking agent, which typically is water soluble
and/or water dispersable, may be present as a component in the
film-forming composition in an amount ranging from 0 to at least 10
percent by weight, or at least 10 to at least 20 percent by weight,
or from at least 20 to at least 30 percent by weight, based on
total resin solids weight in the film-forming composition. In
accordance with certain embodiments of the present invention such a
crosslinking agent may be present in the film-forming composition
in an amount ranging from less than or equal to 70 to less than or
equal to 60 percent by weight, or less than or equal to 60 to less
than or equal to 50 percent by weight, or less than or equal to 50
to less than or equal to 40 percent by weight, based on total resin
solids weight of the film-forming composition. Such a crosslinking
agent can be present in the film-forming composition in an amount
ranging between any combination of these values inclusive of the
recited values.
[0059] In certain embodiments of the present invention, the
film-forming composition may further comprise, in addition to or in
lieu of the aqueous dispersion of polymeric microparticles
described above, an aqueous dispersion of polymeric microparticles
prepared by emulsion polymerization of a monomeric composition
comprising (1) at least 10 percent by weight of one or more vinyl
aromatic compounds; (2) 0.1 to 10 percent by weight of one or more
carboxylic acid functional polymerizable, ethylenically unsaturated
monomers; (3) 0 to 10 percent by weight of one or more
polymerizable monomers having one or more functional groups which
are capable of reacting to form crosslinks; and (4) one or more
polymerizable ethylenically unsaturated monomers, where the weight
percentages are based on total weight of monomers present in the
monomeric composition. Each of (1), (2), (3) and (4) above is
different one from the other, and at least one of (3) and (4) is
present in such a monomeric composition. As used herein, the
phrase, "different one from the other" refers to components that do
not have the same chemical structure as the other components in the
composition. As used herein, the phrase "second polymeric
microparticles" refers to the polymeric microparticles prepared as
described in this paragraph.
[0060] The vinyl aromatic compound (1) from which the second
polymeric microparticles are prepared can comprise any suitable
vinyl aromatic compound known in the art. The one or more
vinyl-aromatic compounds (1) can comprise, for example, a compound
selected from styrene, alph-methyl styrene, vinyl toluene,
para-hydroxy styrene and mixtures thereof.
[0061] The vinyl aromatic compound (1) can be present in the
monomeric composition from which the second polymeric
microparticles are prepared in an amount of at least 10 percent by
weight, or at least 20 percent by weight, or at least 30 percent by
weight, or at least 40 percent by weight, based on total weight of
monomers present in the monomeric composition. The vinyl aromatic
compound (1) also can be present in the monomeric composition from
which the second polymeric microparticles are prepared in an amount
of not more than 98 percent by weight, or not more than 80 percent
by weight, or not more than 70 percent by weight, or not more than
60 percent by weight, based on total weight of monomers present in
the monomeric composition. The amount of vinyl aromatic compound
(1) present in the monomeric composition from which the second
polymeric microparticles are prepared can range between any
combination of the recited values, inclusive of the recited values.
It will be understood by those skilled in the art that the amount
of the vinyl aromatic compound (1) used to prepare the second
polymeric microparticles is determined by the properties desired to
be incorporated into the second polymeric microparticles and/or the
compositions containing such microparticles.
[0062] The one or more carboxylic acid functional, polymerizable,
ethylenically unsaturated monomers (2) from which the second
polymeric microparticles are prepared can comprise any of the
ethylenically unsaturated carboxylic acid functional monomers known
in the art, including, where applicable, anhydrides thereof. The
carboxylic acid functional, polymerizable, ethylenically
unsaturated monomer (2) can comprise, for example, one or more
monomers selected from acrylic acid, methacrylic acid, itaconic
acid, fumaric acid, maleic acid, anhydrides thereof (where
applicable) and mixtures thereof. Non-limiting examples of
anhydrides suitable for use as the one or more carboxylic acid
functional, polymerizable, ethylenically unsaturated monomers (2)
include maleic anhydride, fumaric anhydride, itaconic anhydride,
methacrylic anhydride, and mixtures thereof.
[0063] The one or more carboxylic acid functional, polymerizable,
ethylenically unsaturated monomers (2) can be present in the
monomeric composition from which the second polymeric
microparticles are prepared in an amount of 0 percent by weight, or
at least 0.5 percent by weight, or at least 1 percent by weight,
based on total weight of monomers present in the monomeric
composition. The carboxylic acid functional, polymerizable,
ethylenically unsaturated monomer (2) also can be present in the
monomeric composition from which the polymeric microparticles are
prepared in an amount of not more than 10 percent by weight, or not
more than 8 percent by weight, or not more than 5 percent by
weight, based on total weight of monomers present in the monomeric
composition. The amount of the one or more carboxylic acid
functional, polymerizable, ethylenically unsaturated monomers (2)
present in the monomeric composition from which the second
polymeric microparticles are prepared can range between any
combination of the recited values, inclusive of the recited values.
It will be understood by those skilled in the art that the amount
of the one or more carboxylic acid functional, polymerizable,
ethylenically unsaturated monomers (2) used to prepare the second
polymeric microparticles is determined by the properties desired to
be incorporated into the second polymeric microparticles and/or the
compositions containing such microparticles.
[0064] The one or more polymerizable monomer(s) (3) having one or
more functional groups that are capable of reacting to form
crosslinks from which the second polymeric microparticles are
prepared can include any of the art recognized polymerizable
monomers that have reactive functional groups capable of reacting
either during the polymerization process with a mutually reactive
functional group(s) present on any of the other monomers present in
the monomeric composition, or, alternatively, after the monomer has
been polymerized, for example, with mutually reactive functional
groups present on one or more of the film-forming composition
components. As used herein, "functional groups that are capable of
reacting to form crosslinks after polymerization" refer to, for
example, functional groups on a first polymer molecule that may
react under appropriate conditions to form covalent bonds with
mutually reactive functional groups on a second polymer molecule,
for example a crosslinking agent molecule, or different polymer
molecules present in the film-forming composition.
[0065] In certain embodiments of the present invention, the one or
more polymerizable monomers (3) having functional groups capable of
reacting to form crosslinks from which the second polymeric
microparticles are prepared may comprise any of a variety of
reactive functional groups including, but not limited to, those
selected from amide groups, hydroxyl groups, amino groups, epoxy
groups, thiol groups, isocyanate groups, carbamate groups, and
mixtures thereof.
[0066] In addition, the one or more polymerizable monomers (3) from
which the second polymeric microparticles are prepared can comprise
a compound selected from N-alkoxymethyl amides, N-methylolamides,
lactones, lactams, mercaptans, hydroxyls, epoxides, and the like.
Examples of such monomers include, but are not limited to
y-(meth)acryloxytrialkoxysilane, N-methylol(meth)acrylamide,
N-butoxymethyl(meth)acrylamide, (meth)acryliclactones,
N-substituted (meth)acrylamide lactones, (meth)acryliclactams,
N-substituted (meth)acrylamide lactams, glycidyl (meth)acrylate,
allyl glycidyl ether, and mixtures thereof.
[0067] The one or more polymerizable monomers (3) can be present in
the monomeric composition from which the second polymeric
microparticles are prepared in an amount of 0 percent by weight, or
at least 0.5 percent by weight, or at least 1 percent by weight,
based on total weight of monomers present in the monomeric
composition. The one or more polymerizable monomers (3) also can be
present in the monomeric composition from which the second
polymeric microparticles are prepared in an amount of not more than
10 weight percent, or not more than 8 percent by weight, or not
more than 5 percent by weight, based on total weight of monomers
present in the monomeric composition. The amount of the one or more
polymerizable monomers (3) present in the monomeric composition
from which the second polymeric microparticles are prepared can
range between any combination of the recited values, inclusive of
the recited values. It will be understood by those skilled in the
art that the amount of the one or more polymerizable monomers (3)
used to prepare the second polymeric microparticles is determined
by the properties desired to be incorporated into the second
polymeric microparticles and/or the film-forming compositions
containing such microparticles.
[0068] The one or more polymerizable ethylenically unsaturated
monomer (4) from which the second polymeric microparticles are
prepared can be any of the art recognized ethylenically unsaturated
monomers, provided that the polymerizable ethylenically unsaturated
monomer (4) is different from any of the aforementioned monomers
(1), (2), and (3). Polymerizable ethylenically unsaturated monomers
suitable for use as the monomer (4) which, optionally, make up the
remainder of the monomeric composition used to prepare the second
polymeric microparticles, and which are different from the monomers
(1), (2) and (3), may include any suitable polymerizable
ethylenically unsaturated monomer capable of being polymerized in a
emulsion polymerization system and does not substantially affect
the stability of the emulsion or the polymerization process.
[0069] Suitable polymerizable ethylenically unsaturated monomers
include, but are not limited to, alkyl esters of (meth)acrylic acid
such as methyl(meth)acrylate, ethyl(meth)acrylate,
propyl(meth)acrylate, N-butyl(meth)acrylate, t-butyl(meth)acrylate,
2-ethylhexyl(meth)acrylate, isobornyl (meth)acrylate,
lauryl(meth)acrylate, cyclohexyl(meth)acrylate, and
3,3,5-trimethylcyclohexyl(meth)acrylate.
[0070] The one or more polymerizable ethylenically unsaturated
monomers (4) from which the second polymeric microparticles are
prepared also can include hydroxy-functional ethylenically
unsaturated monomers, for example, a compound selected from
hydroxyethyl(meth)acrylate, hydroxybutyl(meth)acrylate,
hydroxypropyl(meth)acrylate, dimethylaminoethyl (meth)acrylate,
allyl glycerol ether, methallyl glycerol ether, and mixtures
thereof.
[0071] In certain embodiments of the present invention, the one or
more polymerizable ethylenically unsaturated monomers (4) from
which the second polymeric microparticles are prepared can comprise
one or more ethylenically unsaturated, beta-hydroxy ester
functional monomers. Such monomers can be derived from the reaction
of an ethylenically unsaturated acid functional monomer, such as
any of the monocarboxylic acids described above, e.g., acrylic
acid, and an epoxy compound which does not participate in the free
radical initiated polymerization with such unsaturated acid
functional monomer. Examples of such epoxy compounds include
glycidyl ethers and esters. Suitable glycidyl ethers include
glycidyl ethers of alcohols and phenols such as butyl glycidyl
ether, octyl glycidyl ether, phenyl glycidyl ether and the like.
Suitable glycidyl esters include those commercially available from
Shell Chemical Company under the tradename CARDURA E; and from
Exxon Chemical Company under the tradename GLYDEXX-10.
Alternatively, the beta-hydroxy ester functional monomers can be
prepared from an ethylenically unsaturated, epoxy functional
monomer, for example glycidyl(meth)acrylate and allyl glycidyl
ether, and a saturated carboxylic acid, such as a saturated
monocarboxylic acid, for example isostearic acid.
[0072] The one or more ethylenically unsaturated polymerizable
monomers (4) can be present in the monomeric composition from which
the second polymeric microparticles are prepared in an amount of 0
percent by weight, or at least 0.5 percent by weight, or at least 1
percent by weight, or at least 10 weight percent, or at least 20
weight percent based on total weight of monomers present in the
monomeric composition. The one or more ethylenically unsaturated
polymerizable monomers (4) also can be present in the monomeric
composition from which the second polymeric microparticles are
prepared in an amount of not more than 60 percent by weight, or not
more than 50 percent by weight, or not more than 45 percent by
weight, or not more than 40 percent by weight, based on total
weight of monomers present in the monomeric composition. The amount
of the one or more ethylenic ally unsaturated polymerizable
monomers (4) present in the monomeric composition from which the
second polymeric microparticles are prepared can range between any
combination of the recited values, inclusive of the recited values.
It will be understood by those skilled in the art that the amount
of the one or more ethylenically unsaturated polymerizable monomers
(4) used to prepare the second polymeric microparticles is
determined by the properties desired to be incorporated into the
second polymeric microparticles and/or the film-forming
compositions comprising such microparticles.
[0073] The one or more ethylenically unsaturated polymerizable
monomers (4) from which the second polymeric microparticles are
prepared may comprise a crosslinking monomer having two or more
sites of reactive unsaturation, or any of the previously mentioned
monomers having functional groups capable of reacting to form a
crosslink after polymerization. Suitable monomers having two or
more sites of reactive unsaturation can include, but are not
limited to, one or more of ethylene glycol di(meth)acrylate,
triethylene glycol di(meth)acrylate, tetraethylene glycol
di(meth)acrylate, 1,3-butylene glycol di(meth)acrylate,
trimethylolpropane tri(meth)acrylate, 1,4-butanediol
di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,6-hexanediol
di(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol
tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, glycerol
di(meth)acrylate, glycerol allyloxy di(meth)acrylate,
1,1,1-tris(hydroxymethyl)ethane di(meth)acrylate,
1,1,1-tris(hydroxymethy- l)ethane tri(meth)acrylate,
1,1,1-tris(hydroxymethyl)propane di(meth)acrylate,
1,1,1-tris(hydroxymethyl)propane tri(meth)acrylate, triallyl
cyanurate, triallyl isocyanurate, triallyl trimellitate, diallyl
phthalate, diallyl terephthalte, divinyl benzene, methylol
(meth)acrylamide, triallylamine, and
methylenebis(meth)acrylamide.
[0074] As mentioned above, the aqueous dispersion of second
polymeric microparticles, if present, is prepared by well-known
emulsion polymerization techniques. For example the monomeric
composition may be prepared by admixing monomers (1), with monomers
(2); and/or (3) and/or (4). The monomeric composition is dispersed
in the aqueous continuous phase under high shear to form stable
monomer droplets and/or micelles as would be expected under typical
emulsion polymerization techniques. Emulsifiers, protective
colloids, and/or surface active agents as are well known in the art
may be included to stabilize or prevent coagulation or
agglomeration of the monomer droplets during the polymerization
process. The aqueous dispersion of second polymeric microparticles
is then subjected to radical polymerization conditions to
polymerize the monomers within the droplets or micelles.
[0075] Suitable emulsifiers and protective colloids include, but
are not limited to, high molecular weight polymers such as
hydroxyethyl cellulose, methyl cellulose, polyacrylic acid,
polyvinyl alcohol, and the like. Also, materials such as
base-neutralized acid functional polymers can be employed for this
purpose. Suitable surface active agents include any of the well
known anionic, cationic or nonionic surfactants or dispersing
agents. Mixtures of such materials can be used in the aqueous
dispersion of second polymeric microparticles.
[0076] Suitable cationic dispersion agents that may be used with
the aqueous dispersion of second polymeric microparticles include,
but are not limited to, lauryl pyridinium chloride, cetyldimethyl
amine acetate, and alkyldimethylbenzylammonium chloride, in which
the alkyl group has from 8 to 18 carbon atoms. Suitable anionic
dispersing agents include, but are not limited to alkali fatty
alcohol sulfates, such as sodium lauryl sulfate, and the like;
arylalkyl sulfonates, such as potassium isopropylbenzene sulfonate,
and the like; alkali alkyl sulfosuccinates, such as sodium octyl
sulfosuccinate, and the like; and alkali arylalkylpolyethoxyethanol
sulfates or sulfonates, such as sodium octylphenoxypolyethoxyethyl
sulfate, having 1 to 5 oxyethylene units, and the like. Suitable
non-ionic surface active agents include but are not limited to,
alkyl phenoxypolyethoxy ethanols having alkyl groups of from about
7 to 18 carbon atoms and from about 6 to about 60 oxyethylene units
such as, for example, heptyl phenoxypolyethoxyethanols; ethylene
oxide derivatives of long chained carboxylic acids such as lauric
acid, myristic acid, palmitic acid, oleic acid, and the like, or
mixtures of acids such as those found in tall oil containing from 6
to 60 oxyethylene units; ethylene oxide condensates of long chained
alcohols such as octyl, decyl, lauryl, or cetyl alcohols containing
from 6 to 60 oxyethylene units; ethylene oxide condensates of
long-chain or branched chain amines such as dodecyl amine,
hexadecyl amine, and octadecyl amine, containing from 6 to 60
oxyethylene units; and block copolymers of ethylene oxide sections
combined with one or more hydrophobic propylene oxide sections.
[0077] A free radical initiator typically is used in the emulsion
polymerization process. Any suitable free radical initiator may be
used. Suitable free radical initiators include, but are not limited
to, thermal initiators, photinitiators and oxidation-reduction
initiators, all of which may be otherwise categorized as being
water-soluble initiators or non-water-soluble initiators. Examples
of thermal initiators include, but are not limited to, azo
compounds, peroxides and persulfates. Suitable persulfates include,
but are not limited to, sodium persulfate and ammonium persulfate.
Oxidation-reduction initiators may include, as non-limiting
examples, persulfate-sullfite systems as well as systems utilizing
thermal initiators in combination with appropriate metal ions such
as iron or copper.
[0078] Suitable azo compounds include, but are not limited to,
non-water-soluble azo compounds, such as
1-1'-azobiscyclohexanecarbonitri- le, 2-2'-azobisisobutyronitrile,
2-2'-azobis(2-methylbutyronitrile), 2-2'-azobis(propionitrile),
2-2'-azobis(2,4-dimethylvaleronitrile), 2-2'-azobis(valeronitrile),
2-(carbamoylazo)-isobutyronitrile and mixtures thereof, and
water-soluble azo compounds, such as azobis tertiary alkyl
compounds, which include, but are not limited to,
4-4'-azobis(4-cyanovaleric acid),
2-2'-azobis(2-methylpropionamidine)dihy- drochloride,
2,2'-azobis[2-methyl-N-(2-hydroxyethyl)propionamide],
4,4'-azobis(4-cyanopentanoic acid),
2,2'-azobis(N,N'-dimethyleneisobutyra- midine),
2,2'-azobis(2-amidinopropane) dihydrochloride,
2,2'-azobis(N,N'-dimethyleneisobutyramidine)dihydrochloride and
mixtures thereof.
[0079] Suitable peroxides include, but are not limited to, hydrogen
peroxide, methyl ethyl ketone peroxides, benzoyl peroxides,
di-t-butyl peroxides, di-t-amyl peroxides, dicumyl peroxides,
diacyl peroxides, decanoyl peroxide, lauroyl peroxide,
peroxydicarbonates, peroxyesters, dialkyl peroxides,
hydroperoxides, peroxyketals and mixtures thereof.
[0080] The average particle size of the second polymeric
microparticles may be at least 200 Angstroms, or at least 800
Angstroms, or at least 1000 Angstroms, or at least 1500 Angstroms.
The average particle size of the polymeric microparticles can be no
more than 10,000 Angstroms, or not more than 8000 Angstroms, or not
more than 5000 Angstroms, or not more than 2500 Angstroms. When the
average particle size is too large, the microparticles may tend to
settle from the latex emulsion upon storage. The average particle
size of the polymeric microparticles may be any value or in any
range of values-inclusive of those stated above.
[0081] The average particle size can be measured by photon
correlation spectroscopy as described in International Standard ISO
13321. The average particle size values reported herein are
measured by photon correlation spectroscopy using a Malvern
Zetasizer 3000HSa according to the following procedure.
Approximately 10 mL of ultrafiltered deionized water and 1 drop of
a homogenous test sample are added to a clean 20 mL vial and then
mixed. A cuvet is cleaned and approximately half-filled with
ultrafiltered deionized water, to which about 3-6 drops of the
diluted sample is added. Once any air bubbles are removed, the
cuvet is placed in the Zetasizer 3000HSa to determine if the sample
is of the correct concentration using the Correlator Control window
in the Zetasizer Software (100 to 400 KCts/sec). Particle size
measurements are then made with the Zetasizer 3000HSa.
[0082] The aqueous dispersion of second polymeric microparticles
can, for example, be present in the film-forming composition in an
amount of at least 1 percent by weight, or at least 2 percent by
weight, or at least 5 percent by weight, based on total weight of
resin solids present in the film-forming composition. Also, the
aqueous dispersion of second polymeric microparticles can be
present in the film-forming composition in an amount of not more
than 20 percent by weight, or not more than 15 percent by weight,
or not more than 10 percent by weight based on total weight of
resin solids present in the film-forming composition. The amount of
the aqueous dispersion of second polymeric microparticles present
in the film-forming composition can range between any combination
of these values inclusive of the recited values.
[0083] The substantially organic solvent-free film-forming
compositions of the present invention can be thermoplastic
film-forming compositions, or, alternatively, thermosetting
compositions. As used herein, by "thermosetting composition" is
meant one that "sets" irreversibly upon curing or crosslinking,
wherein the polymer chains of the polymeric components are joined
together by covalent bonds. This property is usually associated
with a cross-linking reaction of the composition constituents often
induced, for example, by heat or radiation. See Hawley, Gessner G.,
The Condensed Chemical Dictionary, Ninth Edition., page 856;
Surface Coatings, vol. 2, Oil and Colour Chemists' Association,
Australia, TAFE Educational Books (1974). Curing or crosslinking
reactions also may be carried out under ambient conditions. Once
cured or crosslinked, a thermosetting composition will not melt
upon the application of heat and is insoluble in solvents. By
contrast, a "thermoplastic composition" comprises polymeric
components that are not joined by covalent bonds and thereby can
undergo liquid flow upon heating and are soluble in solvents. See
Saunders, K. J., Organic Polymer Chemistry, pp. 4142, Chapman and
Hall, London (1973).
[0084] The film-forming compositions can contain, in addition to
the components described above, a variety of other adjuvant
materials. If desired, other resinous materials can be utilized in
conjunction with the aforementioned dispersions of polymeric
microparticles so long as the resultant coating composition is not
detrimentally affected in terms of application, physical
performance and appearance properties.
[0085] The film-forming compositions of the present invention can
further include inorganic and/or inorganic-organic particles, for
example, silica, alumina, including treated alumina (e.g.
silica-treated alumina known as alpha aluminum oxide), silicon
carbide, diamond dust, cubic boron nitride, and boron carbide.
[0086] In certain embodiments, the present invention is directed to
film-forming compositions as previously described wherein the
composition comprises a plurality of inorganic particles. Such
inorganic particles may, for example, be substantially colorless,
such as silica, for example, colloidal silica. Such materials may
provide enhanced mar and scratch resistance. Other suitable
inorganic microparticles include fused silica, amorphous silica,
alumina, colloidal alumina, titanium dioxide, zirconia, colloidal
zirconia and mixtures thereof. Such particles can have an average
particle size ranging from sub-micron size (e.g. nanosized
particles) up to 10 microns depending upon the end use application
of the composition and the desired effect.
[0087] In certain embodiments, the particles comprise inorganic
particles that have an average particle size ranging from 1 to 10
microns, or from 1 to 5 microns prior to incorporation into the
film-forming composition. In other embodiments, the inorganic
particles comprise aluminum oxide having an average particle size
ranging from 1 to 5 microns prior to incorporation into the
film-forming composition. In other embodiments, the inorganic
particles comprise aluminum oxide having an average particle size
ranging from 1 to 5 microns prior to incorporation into the
film-forming composition.
[0088] In certain embodiments, such inorganic particles can, for
example, have an average particle size less than 50 microns prior
to incorporation into the composition. In other embodiments, the
present invention is directed to film-forming compositions as
previously described wherein the inorganic particles have an
average particle size ranging from 1 to less than 1000 nanometers
prior to incorporation into the composition. In other embodiments,
the present invention is directed to film-forming compositions as
previously described wherein the inorganic particles have an
average particle size ranging from 1 to 100 nanometers prior to
incorporation into the composition. In other embodiments, the
present invention is directed to film-forming compositions as
previously described wherein the inorganic particles have an
average particle size ranging from 5 to 50 nanometers prior to
incorporation into the composition. In other embodiments, the
present invention is directed to film-forming compositions as
previously described wherein the inorganic particles have an
average particle size ranging from 5 to 25 nanometers prior to
incorporation into the composition. The particle size may range
between any combination of these values inclusive of the recited
values. These materials may constitute, in certain embodiments of
the present invention, up to 30 percent by weight of the total
weight of the film-forming compositions.
[0089] In certain embodiments of the present invention, the
particles can be present in the composition in an amount ranging
from 0.05 to 5.0 percent by weight, or from 0.1 to 1.0 weight
percent; or from 0.1 to 0.5 weight percent based on total weight of
the film-forming composition. The amount of particles present in
the composition can range between any combination of these values
inclusive of the recited values.
[0090] The film-forming compositions also may contain a catalyst to
accelerate the cure reaction, for example, between the blocked
polyisocyanate curing agent and the reactive hydroxyl groups of the
polymeric microparticules comprising the dispersion. Examples of
suitable catalysts include organotin compounds such as dibutyl tin
dilaurate, dibutyl tin oxide and dibutyl tin diacetate. Catalysts
suitable for promoting the cure reaction between an aminoplast
curing agent and the reactive hydroxyl and/or carbamate functional
groups of the thermosettable dispersion include acidic materials,
for example, acid phosphates such as phenyl acid phosphate, and
substituted or unsubstituted sulfonic acids such as dodecylbenzene
sulfonic acid or paratoluene sulfonic acid. The catalyst often is
present in an amount ranging from 0.1 to 5.0 percent by weight, or,
in some cases, 0.5 to 1.5 percent by weight, based on the total
weight of resin solids present in the film-forming composition.
[0091] Other additive ingredients, for example, plasticizers,
surfactants, thixotropic agents, anti-gassing agents, flow
controllers, anti-oxidants, UV light absorbers and similar
additives conventional in the art can be included in the
compositions of the present invention. These ingredients typically
are present in an amount of up to about 40 percent by weight based
on the total weight of resin solids.
[0092] In certain embodiments of the present invention, the
film-forming composition forms a generally continuous film at
ambient temperature (approximately 23-28.degree. C. at 1 atm
pressure). A "generally continuous film" is formed upon coalescence
of the applied coating composition to form a uniform coating upon
the surface to be coated. By "coalescence" is meant the tendency of
individual particles or droplets of the coating composition, such
as would result upon atomization of a liquid coating when spray
applied, to flow together thereby forming a continuous film upon
the substrate which is substantially free from voids or areas of
very thin film thickness between the coating particles.
[0093] The film-forming compositions of the present invention also
may, in certain embodiments, be formulated to include one or more
pigments or fillers to provide color and/or optical effects, or
opacity. Such pigmented film-forming compositions may be suitable
for use in multi-component composite coatings as discussed below,
for example, as a primer coating or as a pigmented base coating
composition in a color-plus-clear system, or as a monocoat
topcoat.
[0094] The solids content of the film-forming composition generally
ranges from 20 to 75 percent by weight, or 30 to 65 percent by
weight, or 40 to 55 percent by weight, based on the total weight of
the film-forming composition.
[0095] As aforementioned, the present invention is also directed to
multi-layer composite coatings. The multi-layer composite coating
compositions of the present invention comprise a base-coat
film-forming composition serving as a basecoat (often a pigmented
color coat) and a film-forming composition applied over the
basecoat serving as a topcoat (often a transparent or clear coat).
At least one of the basecoat film-forming composition and the
topcoat film-forming composition comprises the film-forming
composition of the present invention. The film-forming composition
of the basecoat can be any of the compositions useful in coatings
applications, including any of the previously described
film-forming compositions in accordance with the present invention.
The film-forming composition of the basecoat comprises a resinous
binder and, often, one or more pigments to act as the colorant.
Particularly useful resinous binders are acrylic polymers,
polyesters, including alkyds and polyurethanes such as any of those
discussed in detail above.
[0096] The resinous binders for the basecoat can be organic
solvent-based materials such as those described in U.S. Pat. No.
4,220,679, note column 2 line 24 continuing through column 4, line
40, which is incorporated herein by reference. Also, water-based
coating compositions such as those described in U.S. Pat. No.
4,403,003, U.S. Pat. No. 4,147,679 and U.S. Pat. No. 5,071,904
(incorporated herein by reference) can be used as the binder in the
basecoat composition.
[0097] The basecoat composition can contain pigments as colorants.
Suitable metallic pigments include aluminum flake, copper or bronze
flake and metal oxide coated mica. Besides the metallic pigments,
the basecoat compositions can contain non-metallic color pigments
conventionally used in surface coatings including inorganic
pigments such as titanium dioxide, iron oxide, chromium oxide, lead
chromate, and carbon black; and organic pigments such as, for
example, phthalocyanine blue and phthalocyanine green.
[0098] Optional ingredients in the basecoat composition include
those which are well known in the art of formulating surface
coatings, such as surfactants, flow control agents, thixotropic
agents, fillers, anti-gassing agents, organic co-solvents,
catalysts, and other customary auxiliaries. Examples of these
materials and suitable amounts are described in U.S. Pat. Nos.
4,220,679, 4,403,003, 4,147,769 and 5,071,904, which are
incorporated herein by reference.
[0099] The basecoat compositions can be applied to the substrate by
any conventional coating technique such as brushing, spraying,
dipping or flowing, but they are most often applied by spraying.
The usual spray techniques and equipment for air spraying, airless
spray and electrostatic spraying in either manual or automatic
methods can be used.
[0100] During application of the basecoat to the substrate, the
film thickness of the basecoat formed on the substrate often ranges
from 0.1 to 5 mils (2.54 to about 127 micrometers), or 0.1 to 2
mils (about 2.54 to about 50.8 micrometers).
[0101] After forming a film of the basecoat on the substrate, the
basecoat can be cured or alternately given a drying step in which
solvent is driven out of the basecoat film by heating or an air
drying period before application of the clear coat. Suitable drying
conditions will depend on the particular basecoat composition, and
on the ambient humidity if the composition is water-borne, but
often, a drying time of from 1 to 15 minutes at a temperature of
75.degree. to 200.degree. F. (21.degree. to 93.degree. C.) will be
adequate.
[0102] The solids content of the base coating composition often
generally ranges from 15 to 60 weight percent, or 20 to 50 weight
percent.
[0103] The topcoat, which often is a transparent composition, is
often applied to the basecoat by spray application, however, the
topcoat can be applied by any conventional coating technique as
described above. Any of the known spraying techniques can be used
such as compressed air spraying, electrostatic spraying and either
manual or automatic methods. As mentioned above, the topcoat can be
applied to a cured or to a dried basecoat before the basecoat has
been cured. In the latter instance, the two coatings are then
heated to cure both coating layers simultaneously. Curing
conditions can range from 265.degree. to 350.degree. F.
(129.degree. to 175.degree. C.) for 20 to 30 minutes. The topcoat
thickness (dry film thickness) typically is 1 to 6 mils (about 25.4
to about 152.4 micrometers).
[0104] During application of the topcoat to the base coated
substrate, ambient relative humidity generally can range from about
30 to about 80 percent, preferably about 50 percent to 70
percent.
[0105] In certain embodiments, after the basecoat is applied (and
cured, if desired), multiple layers of clear topcoats can be
applied over the basecoat. This is generally referred to as a
"clear-on-clear" application. For example, one or more layers of a
conventional transparent coat can be applied over the basecoat and
one or more layers of transparent coating of the present invention
applied thereon. Alternatively, one or more layers of a transparent
coating of the present invention can be applied over the basecoat
as an intermediate topcoat, and one or more conventional
transparent coatings applied thereover.
[0106] The multi-layer composite coating compositions of the
present invention can be applied over virtually any substrate
including wood, metals, glass, cloth, plastic, foam, including
elastomeric substrates and the like. They are particularly useful
in applications over metals and elastomeric substrates that are
utilized in the manufacture of motor vehicles. The substantially
organic solvent-free film-forming compositions of the present
invention can provide multi-component composite coating systems
that have appearance and performance properties commensurate with
those provided by solvent-based counterparts with appreciably less
volatile organic emissions during application.
[0107] Illustrating the invention are the following examples,
which, however, are not to be considered as limiting the invention
to their details. Unless otherwise indicated, all parts and
percentages in the following examples, as well as throughout the
specification, are by weight.
EXAMPLES
[0108] The following Examples A and B describe the preparation of
resinous binders for use in the preparation of compositions of the
present invention. Example C describes the preparation of
water-dilutable additive materials for use in compositions of the
present invention. Example D describes the preparation of a
functional polysiloxane additive for use in compositions of the
present invention. Example E describes the preparation of aqueous
dispersions of polymeric microparticles prepared by emulsion
polymerization for use in the preparation of compositions of the
present invention. Examples F and G describes the preparation of
film-forming compositions of the present invention that include
materials prepared in Examples A, C and D. Example H describes the
preparation of film-forming compositions of the present invention
that include materials prepared in Examples B, C, D, and E.
Example A
Resinous Binder A
[0109] A resinous binder was prepared as described below from the
ingredients of Table 1. The amounts listed are the total parts by
weight in grams and the amount within parenthesis are total parts
by weight solids, in grams.
1 TABLE 1 Ingredient Amount Charge 1 Acrylic.sup.1 2316.2 (1466.2)
TRIXENE DP9B/1504.sup.2 299.2 (209.5) MIBK.sup.3 53.7 (0) Charge 2
TINUVIN 400.sup.4 73.9 (62.8) TINUVIN 123.sup.5 20.9 (20.9)
BYK-390.sup.6 20.9 (10.5) Polybutylacrylate.sup.7 10.5 (6.3)
Dibutyltin Dilaurate 4.8 (4.8) Dimethyl Ethanolamine 26.3 (0)
SURFYNOL 2502.sup.8 14.7 (14.7) Charge 3 MIBK 53.7 (0) Charge 4
Dimethyl Ethanolamine 6.6 (0) Deionized Water 3022.0 (0) Charge 5
Deionized Water 100.0 (0) Charge 6 FOAM KILL 649.sup.9 1.7 (1.7)
.sup.1Acrylic resin (30.3% styrene, 19.9% hydroxyethyl
methacrylate; 28.7% CARDURA E (glycidyl neodecanoate available from
Shell Chemical Co.), 11.0% acrylic acid, and 10.15% 2-ethylhexyl
acrylate) .sup.2Blocked isocyanate available from Baxenden Chemical
Ltd., Lancashire, England. .sup.3Methyl isobutyl ketone .sup.4Light
stabilizer available from Ciba Specialty Chemicals, Basel,
Switzerland .sup.5Light stabilizer available from Ciba Specialty
Chemicals, Basel, Switzerland .sup.6Acrylate leveling additive
available from BYK-Chemie USA Inc., Wallingford, Connecticut
.sup.760% solids in styrene .sup.8Surfactant available from Air
Products and Chemicals, Inc., Allentown, Pennsylvania
.sup.9Defoamer available from Crucible Chemical
[0110] Charge 1 and then charge 2 were added to a flask at ambient
conditions and mixed until homogeneous. The temperature was
increased to 25.degree. C. At that temperature, the mixture was
added to a flask containing charge 4, by dripping the mixture into
the flask over one hour. Charge 3 was then added to the flask and
the contents were held for 30 minutes. The resulting pre-emulsion
was passed once through a Microfluidizer.RTM. M11T (available from
Microfluidics Corp., Newton, Mass.) at 11,500 psi with cooling
water to maintain the pre-emulsion at approximately room
temperature. Charge 5 was then passed through the Microfluidizer to
rinse. Solvents were removed by vacuum distillation. The final
composition contained about 46 weight % solids with Charge 6 being
added as needed during vacuum distillation.
Example B
Resinous Binder B
[0111] A resinous binder was prepared as described below from the
ingredients of Table 2. The amounts listed are the total parts by
weight in grams and the amount within parenthesis are total parts
by weight solids, in grams.
2 TABLE 2 Ingredient Amount Charge 1 Acrylic.sup.10 2182.8 (1382.4)
Crosslinker.sup.11 145.7 (126.8) Flex Acrylic.sup.12 330.0 (250.8)
MIBK 47.3 (0) Charge 2 TINUVIN 400 54.7 (46.5) TINUVIN 123 18.6
(18.6) BYK-337.sup.13 0.4 (0.1) DiMethyl Ethanolamine 36.7 (0)
Dimethyl Ethanolamine 5.4 (0) SURFYNOL 2502 13.8 (13.8) Charge 3
MIBK 47.3 (0) Charge 4 Dimethyl Ethanolamine 9.2 (0) Deionized
Water 3151.0 (0) Charge 5 Deionized Water 88.0 (0) Charge 6 FOAM
KILL 649.sup.9 1.5 (1.5) .sup.10Acrylic resin (28.67% styrene,
19.9% hydroxyethyl methacrylate, 28.6% CARDURA E (glycidyl
neodecanoate available from Shell Chemical Co.), 12.75% acrylic
acid, and 10.15% 2-ethylhexyl acrylate) .sup.11Blocked isocyanate
(87% solids in MIBK) produced by charging 1930.0 parts by weight
DESMODUR N3300 (a trimer of hexamethylene diisocyanate available
from Bayer Corporation) to a reactor containing 1.75 parts by
weight dibutyltin dilaurate and 436.8 parts by weight MIBK. 540.7
parts by weight of benzyl alcohol was then added over 90 minutes
keeping the temperature # below 80.degree. C. After completion of
this addition, the reaction temperature was maintained at
80.degree. C. and monitored by infrared spectroscopy for
disappearance of the isocyanate band. .sup.12Acrylic resin (31.4%
CARDURA E (glycidyl neodecanoate available from Shell Chemical
Co.), 5.5% isostearic acid, 12.2% methyl methacrylate, 10.3%
styrene, 17.1% 2-ethylhexyl acrylate, 12.9% hydroxyethyl acrylate,
10.6% acrylic acid) .sup.13Solution of a polyether modified
poly-dimethyl-siloxane available from BYK-Chemie USA Inc.,
Wallingford, Connecticut
[0112] Charge 1 and then charge 2 were added to a flask at ambient
conditions and mixed until homogeneous. The temperature was
increased to 25.degree. C. At that temperature, the mixture was
added to a flask containing charge 4, by dripping the mixture into
the flask over one hour. Charge 3 was then added to the flask and
the contents were held for 30 minutes. The resulting pre-emulsion
was passed once through a Microfluidizer.RTM. M110T (available from
Microfluidics Corp., Newton, Mass.) at 11,500 psi with cooling
water to maintain the pre-emulsion at approximately room
temperature. Charge 5 was then passed through the Microfluidizer to
rinse. Solvents were removed by vacuum distillation. The final
composition contained about 46 weight % solids with Charge 6 being
added as needed during vacuum distillation.
Example C
Water Dilutable Additive C
[0113] Table 3 sets forth the components and amounts for various
water dilutable additives C1 through C12 that were prepared as
described below.
3TABLE 3 Ex- am- Isocyanate Polyethylene ple Isocyanate Equiv-
Methoxypolyethyelene Glycol No. Type alents Glycol Type Equivalents
C1 IPDI.sup.14 1.0 MPEG 2000.sup.20 1.004 C2 IPDI 1.0 MPEG
750.sup.21 1.004 C3 IPDI 1.0 MPEG 550.sup.22 1.004 C4 IPDI 1.0 MPEG
350.sup.23 1.004 C5 TDI.sup.15 1.0 MPEG 2000 1.004 C6
m-TMXDI.sup.16 1.0 MPEG 2000 1.004 C7 HDI.sup.17 1.0 MPEG 2000
1.004 C8 HDI 1.0 MPEG 2000 1.004 Trimer.sup.18 C9 IPDI 1.0 MPEG
2000 1.004 Trimer.sup.19 C10 IPDI 1.0 MPEG 2000/MPEG 750
0.502/0.502 C11 IPDI 1.0 MPEG 2000/MPEG 550 0.502/0.502 C12 IPDI
1.0 MPEG 2000/MPEG 350 0.502/0.502 .sup.14Isophorone Diisocyanate
.sup.15Toluene Diisocyanate .sup.16META-Tetramethylxylylene
Diisocyanate commercially available from CYTEC Industries, Inc.
.sup.17Hexamethylene Diisocyanate .sup.18DEMODUR 3390 commercially
available from Bayer Corporation .sup.19T-1890L commercially
available from DeGussa Corporation .sup.20CARBOWAX MPEG 2000
commercially available from The Dow Chemical Company
.sup.21CARBOWAX MPEG 750 commercially available from The Dow
Chemical Company .sup.22CARBOWAX MPEG 550 commercially available
from The Dow Chemical Company .sup.23CARBOWAX MPEG 350 commercially
available from The Dow Chemical Company
[0114] In each case, the isocyanate, the polyethylene glycol, and
methyl isobutyl ketone were charged to a glass reactor equipped
with an agitator, condenser, thermocouple, and nitrogen blanket.
The charge was heated to 55.degree. C. After complete dissolution
of the charge, a charge of dibutyl tin dilaurate was added (0.05%
by weight based on the total weight of the reactants). The
reactants were then slowly heated over a one-half hour period to
about 90.degree. C. If an exotherm occurred, the reactants were
cooled to 85-90.degree. C. The reaction was monitored by infrared
spectroscopy for disappearance of the isocyanate peak. Deionized
water was then added to the reactor over a 20 minute period to give
a dispersion solids of about 64.5%. The dispersions were held for
one hour at about 70-75.degree. C. under agitation. The product was
then distilled to remove methyl isobutyl ketone and provide a final
dispersion solid of about 40-45%.
Example D
Water Dilutable Additive D
[0115] A reactive functional group-containing polysiloxane was
prepared from a polysiloxane polyol that was prepared as described
below from the mixture of ingredients of Table 4.
4TABLE 4 Equivalent Parts By Weight Ingredients Weight.sup.2
Equivalents (kilograms) Charge I: Trimethylolpropane 174.0.sup.
756.0 131.54 monoallyl ether Charge II: MASILWAX BASE.sup.24
156.7.sup.25 594.8 93.21 Charge III: Chloroplatinic acid 10 ppm
Toluene 0.23 Isopropanol 0.07 .sup.24Polysiloxane-containing
silicon hydride, commercially available from Lubrizol Corporation.
.sup.25Equivalent weight based on mercuric bichloride
determination.
[0116] To a suitable reaction vessel equipped with a means for
maintaining a nitrogen blanket, Charge I and an amount of sodium
bicarbonate equivalent to 20 to 25 ppm of total monomer solids was
added at ambient conditions and the temperature was gradually
increased to 75.degree. C. under a nitrogen blanket. At that
temperature, about 5.0% of Charge II was added under agitation,
followed by the addition of Charge III, equivalent to 10 ppm of
active platinum based on total monomer solids. The reaction was
then allowed to exotherm to 95.degree. C. at which time the
remainder of Charge II was added at a rate such that the
temperature did not exceed 95.degree. C. After completion of this
addition, the reaction temperature was maintained at 95.degree. C.
and monitored by infrared spectroscopy for disappearance of the
silicon hydride absorption band (Si--H, 2150 cm.sup.-1).
[0117] To produce the reactive functional group-containing
polysiloxane, 360.3 grams of the polysiloxane polyol described
above was added to a reaction flask. The polyol was then heated to
60.degree. C. and 84.4 g of m-hexahydrophthalic anhydride was added
over 30 minutes. The reaction was held 3 hours and checked for
complete reaction by IR (disappearance of peak at 1790). The
reaction was then cooled to ambient temperature and 44.7 g of
dimethyl ethanolamine was added over 30 minutes. The reaction was
held at ambient temperature for 15 minutes and 383.6 g of deionized
water added over 3 hours.
Example E
[0118] Additive E--Aqueous Dispersions of Polymeric
Microparticles
[0119] The aqueous dispersions of Polymeric microparticles of
Examples E1 to E9 prepared by emulsion polymerization were prepared
as described below from a mixture of the following ingredients in a
glass reactor equipped with an agitator, a nitrogen blanket, a
monomer feed zone, and a thermocouple.
5 CHARGE 1 Deionized Water 0.15% active weight percent based on
monomer AEROSOL OT75.sup.26 charge Sodium Bicarbonate 0.125% by
weight based on monomer charge .sup.26A 75% solution of
dioctylsodium sulfosuccinate in isoproponal available from CYTEC
Industries, Inc.
[0120]
6 CHARGE 2 Ammonium Persulfate 0.4% by weight based on monomer
charge Water
Charge 3
[0121] Pre-emulsions (weight ratio of monomer to water of 55:45)
were prepared from the monomers listed in Table 5 (weight percent
based on 100 parts monomer) using 0.5% Aerosol OT75 by active
weight based on the monomer charge. The pre-emulsions were prepared
by mixing the monomers with the water and surfactant for 30
minutes.
7TABLE 5 Example Monomer No. Styrene MMA.sup.27 BA.sup.28 AA.sup.29
NMA.sup.30 HEMA.sup.31 PS.sup.32 pH % Gel.sup.33 E1 44.75 44 0 8.5
2 2.5 1480 8.8 88 E2 89.5 0 0 8.5 2 0 1500 7.83 98 E3 45 44.5 0 8.5
2 0 1500 8.85 88 E4 22.38 67.12 0 8.5 2 0 1350 8.62 71 E5 53.25
44.75 0 2 0 0 1300 9.03 2 E6 44.75 42.25 0 8.5 2 2.5 940.sup.8 8.7
-- E7 44.75 0 42.25 8.5 2 0 1800 7.15 98 E8 53.25 0 44.75 2 2 0
1800 9.75 -- E9 90.75 0 0 8.5 1.25 0 1600 8.6 96 .sup.27Methyl
Methacrylate. .sup.28Butyl Methacrylate. .sup.29Acrylic Acid.
.sup.30A 50% solution of N-Methylolacrylamide in water available
from Cytec Industries, Inc. .sup.31Hydroxy Ethyl Methacrylate.
.sup.32Average particle size measured by photon correlation
spectroscopy using a Malvern Zetasizer 3000Hsa. .sup.33As measured
by digestion of dry particles in acetone. .sup.34The amount of
surfactant was tripled to reduce particle size.
[0122] Charge 1 was heated to about 80.degree. C. under a blanket
of nitrogen. Charge 2 was added at this temperature and held for
five minutes. Charge 3 was added over a three-hour period followed
by a one-hour hold. The reaction was allowed to cool to about less
than 50.degree. C. and a portion of dimethyl amino ethanol in water
(50:50 ratio) was added to increase the pH to at least 7.0. The
final solids of the polymers was about 32%.
Example F1
Film-Forming Compositions Containing Materials From Examples A, C
and D
[0123] Film-forming compositions were prepared as described below
from the components listed in Table 6. Seven film-forming
compositions were prepared for Example F1 by varying the Example C
additive as reflected in Table 7.
8TABLE 6 Component Amount No. Description (grams) 1 Resinous Binder
of Example A 183.5 2 Polysiloxane of Example D 2.13 3
TEXANOL.sup.35 9.0 4 Butyl Acetate.sup.36 3.0 5 Deionized water
29.00 6 Additives of Example C 12.5 7 CYMEL 327.sup.37 12.8 8 CYMEL
303.sup.38 3.0 9 Premix 1 CYMEL 327 5.3 AEROSIL 200.sup.39 0.2 10
Premix 2 Dodecylbenzylsulfonic Acid 0.2 Dimethylethanolamine (50%
in deionized 0.182 water).sup.40 Deionized water 0.160 11 Premix 3
BORCHI Gel LW44.sup.41 0.24 Deionized Water 0.96 .sup.352,2,4
Trimmethyl-1,3 Pentanediol Monoisobuterate available from Dow
Chemical Company .sup.36N-Butyl Acetate available from Dow Chemical
Company .sup.37High Imino Melamine-Formaldehyde Crosslinking Agent
available from Cytec Industries, Inc. .sup.38Hexamethoxymethyl
melamine resin available from Cytec Industries, Inc. .sup.39Silica
commercially available from Degussa Corporation. .sup.40Available
from PPG Industries, Inc. .sup.41Non-ionic, polyurethane based
thickener available from Borchers GmbH
[0124] Premix 1 was prepared by adding the Areosil 200 to the Cymel
327 and stirring. The mixture was added to an EIGER mill to achieve
a grind fineness of 7+Hegman. Premix 2 was prepared slowly
agitating dodecylbenzylsulfonic acid and adding
demethylehtanolamine (50% in deionized water) and deionized water.
Premix 3 was prepared by stirring the Borchi Gel LW44 and adding
deionized water until a uniform consistency was achieved.
[0125] The film-forming composition was prepared by charging
component 1 and then adding component 2 under agitation until fully
incorporated. Then, under moderate agitation, components 3 to 11
were added. The final compositions had a solids content of 45% and
a viscosity of 30 seconds using a #4 Din cup.
Test Substrates
[0126] The test substrates were ACT cold-roll steel panels
(4".times.12") supplied by ACT Laboratories, Inc. and were
electrocoated with a cationic electrodepositable primer
commercially available from PPG Industries, Inc. as ED-6060. The
panels were then spray coated in two coats with EWB Reflex Silver
Basecoat commercially available from PPG Industries, Inc. to film
thicknesses ranging from 0.4 to 0.6 mils. The basecoat was flashed
for 5 minutes at ambient temperature and then baked for 5 minutes
at 176.degree. F. (80.degree. C.). The substrate was then cooled to
ambient temperature. After cooling, film-forming compositions of
Example F1 were spray applied, with a target film thickness of 1.3
to 1.7 mils, in two coats without flash time between coats. The
substrates coated with the Example F1 compositions were flashed for
2 minutes at ambient temperature and then the coated substrates
were placed in an oven at 150.degree. C., prior to increasing the
oven temperature to 311.degree. C. The coated substrates were cured
for 23 minutes in an oven set at 311.degree. C. Appearance and
properties for the coatings are reported below in Table 7.
9TABLE 7 Water Dilutable Coating Additive C % 20.degree. Gloss
Retained Example No. Example No. Gloss.sup.42 Haze.sup.42
DOI.sup.43 LW.sup.44 SW.sup.44 after scratch testing.sup.45 F1a C1
100 345 76 4 14 56 F1b C4 99 331 78 4 15 40 F1c C10 99 322 81 3 15
41 F1d C12 99 350 75 8 14 46 F1e C3 99 339 81 4 17 44 F1f C11 100
350 77 4 13 46 F1g C2 99 330 83 3 15 43 .sup.42Gloss and haze of
test panels coated as described above was determined at a
20.degree. angle using a Micro-TriGloss Reflectometer available
from BYK Gardner, Inc. .sup.43Distinctness of image ("DOI") of
sample panels was determined using a Dorigon II DOI Meter, which is
commercially available from Hunter Lab, where a higher value
indicates better coating appearance on the test panel.
.sup.44Smoothness of the coated test panels was measured using a
Byk Wavescan in which results are reported as long wave and short
wave numbers where lower values mean smoother films. .sup.45Coated
panels were subjected to scratch testing by linearly scratching the
coated surface with a weighted abrasive paper for ten double rubs
using an Atlas AATCC Scratch Tester, Model CM-5, available from
Atlas Electrical Devices Company of Chicago, Illinois. The abrasive
paper used was 3M 281Q WETORDRY .TM. PRODUCTION .TM. 9 micron
polishing paper sheets, which are commercially available from 3M
Company of St. Paul, Minnesota. # Panels were then rinsed with tap
water and carefully patted dry with a paper towel. The 20.degree.
gloss was measured (using the same gloss meter as that used for the
initial 20.degree. gloss) on the scratched area of each test panel.
Using the lowest 20.degree. gloss reading from the scratched area,
the scratch results are reported as the percent of the initial
gloss retained after scratch testing using the following
calculation: 100% * (scratched)/(initial gloss). # Higher values
for percent of gloss retained are desirable.
Example F2
Film-Forming Compositions Containing Materials From Examples A, C
and D
[0127] Film-forming compositions were prepared as described below
from the components listed in Table 8. The compositions were
prepared in the same manner as the compositions of Example F1
described above. Seven film-forming compositions were prepared for
Example F2 by varying the Example C additive as reflected in Table
9.
10TABLE 8 Component Amount No. Description (grams) 1 Resinous
Binder of Example A 183.5 2 Polysiloxane of Example D 2.13 3
TEXANOL 9.0 4 Butyl Acetate 3.0 5 Deionized water 29.00 6 Additives
of Example C 7.7 7 CYMEL 327 12.8 8 CYMEL 303 3.0 9 Premix 1 CYMEL
327 5.3 AEROSIL 200 0.2 10 Premix 2 Dodecylbenzylsulfonic Acid 0.2
Dimethylethanolamine (50% in deionized 0.182 water) Deionized water
0.160 11 Premix 3 BORCHI Gel LW44 0.24 Deionized Water 0.96
Test Substrates
[0128] The test substrates were prepared in the same manner as is
described in Example F1 above. Appearance and properties for the
coatings of Example 2 are reported below in Table 9. These
properties were measured by the same methods as described above for
the coatings of Example F1.
11TABLE 9 Coating Water % 20.degree. Gloss Ex- Dilutable Retained
ample Additive C after scratch No. Example No. Gloss Haze DOI LW SW
testing F2a C1 100 337 80 3 17 56 F2b C4 96 335 71 6 16 48 F2c C10
99 347 74 5 15 50 F2d C12 99 343 72 5 15 49 F2e C3 99 340 78 4 15
39 F2f C11 99 341 75 4 15 54 F2g C2 99 344 73 5 15 43
Example G
Compositions Containing Materials From Examples A, C1 and D
[0129] Film-forming compositions were prepared as described below
from the components listed in Table 10.
12 TABLE 10 Amount (grams) Component Example Example Example
Example No. Description G1 G2 G3 G4 1 Resinous Binder of Example A
174.6 174.6 174.6 174.6 2 Byk 345.sup.46 0.48 0.48 0.48 0.48 3 Byk
325.sup.47 0.24 0.24 0.24 0.24 4 Polysiloxane of Example D 4.25
4.25 4.25 4.25 5 TEXANOL 10.0 10.0 10.0 10.0 6 Isobutanol 6.0 6.0
6.0 6.0 7 Isostearyl Alcohol 4.0 4.0 4.0 4.0 8 Deionized water 15.0
15.0 15.0 15.0 9a Additive of Example C1 0 2.5 6.3 10.5 9b CYMEL
303 3.1 0 0 0 10 Premix 1 CYMEL 327 19.88 23.5 23.5 23.5 AEROSIL
200 0.4 0.4 0.4 0.4 11 Premix 2 Dodecylbenzylsulfonic Acid 0.196
0.196 0.196 0.196 Dimethylethanolamine (50% in 0.167 0.167 0.167
0.167 deionized water) Deionized water 0.167 0.167 0.167 0.167 12
Premix 3 BORCHI Gel LW44 0.214 0.4 0.4 0.374 Deionized Water 0.856
1.6 1.6 1.496 .sup.46Available from Byk-Chemie, Wallingford, CT.
.sup.47Available from Byk-Chemie, Wallingford, CT.
[0130] Premix 1 was prepared by adding the Areosil 200 to the Cymel
327 and string. The mixture was added to an EIGER mill to achieve a
grind fineness of 7+Hegman. Premix 2 was prepared slowly agitating
dodecylbenzylsulfonic acid and adding demethylehtanolamine (50% in
deionized water) and deionized water. Premix 3 was prepared by
stirring the Borchi Gel LW44 and adding deionized water until a
uniform consistency was achieved.
[0131] The film-forming composition was prepared by charging
components 1 through 3 and then adding component 4 under agitation
until fully incorporated. Then, under moderate agitation,
components 5 to 12 were added. The final compositions had a solids
content of 45% and a viscosity of about 30 seconds using a #4 Din
cup.
Test Substrates
[0132] The test substrates were ACT cold roll steel panels
(4".times.12") supplied by ACT Laboratories, Inc. and were
electrocoated with a cationic electrodepositable primer
commercially available from PPG Industries, Inc. as ED-6060. The
panels were then spray coated in two coats with EWB Obsidian
Schwartz Basecoat commercially available from PPG Industries, Inc.
to film thicknesses ranging from 0.4 to 0.6 mils. The basecoat was
flashed for 5 minutes at ambient temperature and then baked for 5
minutes at 176.degree. F. (80.degree. C.). The substrate was then
cooled to ambient temperature. After cooling, film-forming
compositions of Example G1-G4 were spray applied, with a target
film thickness of 1.3 to 1.7 mils, in two coats without flash time
between coats. The substrates coated with the Example G
compositions were flashed for 2 minutes at ambient temperature and
then the substrates were placed in an oven at 150.degree. C., prior
to increasing the oven temperature to 311.degree. C. The coated
substrates were cured for 23 minutes in an oven set at 311.degree.
C. Appearance and properties for the coatings of Example G are
reported below in Table 11.
13TABLE 11 % 20.degree. Gloss Pop Coating Retained Resistance
Example after scratch microns No. Gloss Haze DOI LW SW testing
pop.sup.48 G1 93 17 87 7.4 15.8 24 35 G2 93 21 92 9.7 18.5 24 40 G3
93 90 20 9.1 16.7 31 42 G4 92 24 92 7.2 17.2 24 45 .sup.48Pop
resistance (measures the ability of the coating to resist the
release of air from the coating composition as it is cured) was
evaluated visually by examining the panels for pops and noting the
film thickness at which the popping begins. This is done by
visually viewing the panel and determining the lowest film build
without significant popping for panels coated with increasing film
thickness along the distance from the top of the panel which had
the # lowest film build. A higher value indicates better resistance
to popping.
Example H
Compositions Containing Materials From Examples B, C, D and E
[0133] Film-forming compositions were prepared as described below
from the components listed in Table 12.
14TABLE 12 Component Amount No. Description (grams) 1 Resinous
Binder of Example B 142.25 2 Microparticles of Example E 4.75 3
Polysiloxane from Example D 2.13 4 TEXANOL 10.0 5 Isosteryl
Alcohol.sup.46 4.0 6 Deionized water 29.00 7 Additive from Example
C1 12.5 8 CYMEL 303 3.0 9 Premix 1 RESIMENE 741.sup.47 12.0 AEROSIL
200 0.24 10 Premix 2 Dodecylbenzylsulfonic Acid 0.2
Dimethylethanolamine (50% in deionized 0.182 water) Deionized water
0.160 11 Premix 3 BORCHI Gel LW44 0.24 Deionized Water 0.96
.sup.46Available from Goldschmidt Chemcial Corp., Hopewell,
Virginia. .sup.47Aminoplast resin available examethoxymethyl
melamine resin available from Cytec Industries, Inc.
[0134] Premix 1 was prepared by adding the AEROSIL 200 to the
RESIMENE 741 and stirring. The mixture was added to an EIGER mill
to achieve a grind fineness of 7+Hegman. Premix 2 was prepared
slowly agitating dodecylbenzylsulfonic acid and adding
demethylehtanolamine (50% in deionized water) and deionized water.
Premix 3 was prepared by stirring the Borchi Gel LW44 and adding
deionized water until a uniform consistency is achieved.
[0135] The film-forming composition was prepared by blending
components 1 and 2 and then adding component 3 under agitation
until fully incorporated. Then, under moderate agitation,
components 3 to 11 are added. The final compositions had a solids
content of 45% and a viscosity of 30 seconds using a #4 Din
cup.
Test-Substrates
[0136] The test substrates were prepared in the same manner as is
described in Example F1. Appearance and properties for the coatings
of Example G are reported below in Table 13. The gloss, haze, DOI,
and LW/SW smoothness were measured by the same methods as described
for the coatings of Example F1.
15TABLE 13 Addi- Pop re- Coating tive E sistance Pop for Exam-
Exam- microns control ple No. ple No. Gloss Haze DOI LW SW
pop.sup.48 each set Control None 95 17 96 4.8 19.2 40 G1 E1 94 14
97 1.6 7.0 50 45 G2 E2 94 17 94 6.3 12.2 100 40 G3 E3 96 16 90 19.3
17.9 45 40 G4 E4 96 17 89 17.7 20.3 48 40 G5 E5 94 14 97 1.6 8 45
45 G6 E6 95 15 95 6.2 17.5 38 41 (with control MG 45) G7 E9 95 15
96 4 22.8 47 45
[0137] It will be readily appreciated by those skilled in the art
that modifications may be made to the invention without departing
from the concepts disclosed in the foregoing description. Such
modifications are to be considered as included within the following
claims unless the claims, by their language, expressly state
otherwise. Accordingly, the embodiments described in detail herein
are illustrative only and are not limiting to the scope of the
invention which is to be given the full breadth of the appended
claims and any and all equivalents thereof.
* * * * *